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PRE-ALGEBRA REVIEW
Chapter 1
1.1 Operations with Whole Numbers, Decimals, and Fractions1.2 Integers and Signed Numbers1.3 Order of Operations1.4 Basic Definitions and Evaluating Expressions1.5 Sets1.6 Closure1.7 Writing Verbal Statements1.8 Properties of Equality1.9 Like Terms
AddingandSubtractionDecimals
Whenaddingandsubtractingnumberswithdecimals,thenumbersshouldbestackedvertically.Alldecimalpointsshouldbelinedupandanyemptyplacevaluesshouldbe;illedwithzeros.Addorsubtracteachcolumnrememberingtocarryorborrowwhereneeded.Thedecimalpointdropsdownandstaysinthesameplacewhereitstarted.
MultiplyingDecimals
Whenmultiplyingnumberswithdecimals,multiplyasusual.Thedecimalpointsdonotneedtobelinedupformultiplication.Attheendmovethedecimalpointontheanswertotheleft,byaddingupthetotalnumberofplaceseachnumberhasafterthedecimalpoint.
DividingDecimals
Whendividingwithdecimals,ifthedivisor(thenumberyouaredividingby)isnotawholenumber,movethedecimalpointtomakeitawholenumber.Movethedecimalpointonthedividend(thenumberyouaredividing)thesamenumberofplacesasthedivisor.Divideasusual,placingthedecimalpointdirectlyabovewhereitisinthedividend.
ImproperFractionsandMixedNumbers
Tochangeanumberfromamixednumbertoanimproperfraction,multiplythedenominatorbythewholenumberthenaddthenumeratortoit.Placethatnumberovertheoriginaldenominator.
Tochangeanumberfromanimproperfractiontoamixednumber,dividethenumeratorbythedenominator.Thequotientbecomesthewholenumber,theremainderbecomesthenumerator,andtheoriginaldenominatorstaysthesame.
Section 1Operations with Whole Numbers, Decimals and Fractions
2
!Example:!!!4!+!4.64!+!12.892!!!! 4.000!!!!!!!!!!!!04.640!!!!+!!!!!12.892!!!!!!!!!!!17.532!!
!Example:!!!! 12.89!–!11.643!!!!!!!12.890!3!!!11.643!!!!!!!!1.247!!
!Example:!4.812!!x!!3.62!!!!!!!!!!!!!!!!!4.812!!!(3!places!after!the!decimal!point)!!!!!!x!!!!!!!3.62!!!(2!places!after!the!decimal!point)!!!!!!!!!!!!!!9624!!!!!!!!!288720!+!!!1443600! !!!!!!17.41944!!(move!decimal!to!the!left!a!total!of!5!places)!!!
Example: 24.396 ÷ 3.8 24.396 is the dividend, 3.8 is the divisor 006.42 38 243.96 -228 159 - 152 76 - 76 0
!Example:!!!4!+!4.64!+!12.892!!!! 4.000!!!!!!!!!!!!04.640!!!!+!!!!!12.892!!!!!!!!!!!17.532!!
Adding Decimals
!Example:!!4 !! !!"#$!!"!!"#$%#&$!!"#$%&'(!!3!!!4!=!12!!12!+!2!=!14!!=!!"! !!!!
Example: into a mixed number 8 R1 2 17 -16 1
!Example:!!4 !! !!"#$!!"!!"#$%#&$!!"#$%&'(!!3!!!4!=!12!!12!+!2!=!14!!=!!"! !!!!Mixed Number to Improper Fraction
AddingandSubtractingwithFractions(CommonDenominator)
Whenaddingandsubtractingwithfractions,youmusthaveacommondenominator.Firstchangeanymixednumbersintoimproperfractions.Ifyouhaveacommondenominator,addthenumeratorstogetherandkeepthedenominatorthesame.Simplifybyremovinganycommonfactorsthenumeratoranddenominatorshare.
AddingandSubtractingwithFractions(UncommonDenominator)
Whenaddingandsubtractingwithfractions,youmusthaveacommondenominator.Firstchangeanymixednumbersintoimproperfractions.Ifyoudonothaveacommondenominator,;indtheleastcommondenominator(LCD-lowestmultipleofthedenominators).MultiplythenumeratoranddenominatorofeachfractionbyanumberthatwouldmakethedenominatorsequaltotheLCD.Onceyouhaveacommondenominator,addthenumeratorstogetherandkeepthedenominatorthesame.Simplifybyremovinganycommonfactorsthenumeratoranddenominatorshare.
MultiplyingFractions
Allmixednumbersshouldbeturnedintoimproperfractions.Cross-simplifythefractionswherepossible.Multiplytheremainingnumerators.Multiplytheremainingdenominators.Simplifyattheendifneeded.
DividingFractions
Allmixednumbersshouldbeturnedintoimproperfractions.Multiplybythereciprocalofthesecondfraction(KEEPthe;irstfraction,CHANGEthesigntomultiplication,FLIPthesecondfraction).Cross-simplifythefractionswherepossible.Multiplytheremainingnumerators.Multiplytheremainingdenominators.Simplifyattheendifneeded.
PracticeProblems1
PracticeProblems2 3
Example:
!Example:!!!! − !
!!!
!!!!!!!!!!!!!!! − !
!! = !
!!!
!!!
Example:
Adding with a Common Denominator
Adding and Subtracting
Fractions with Uncommon
Denominators
Multiplying Fractions
Dividing Fractions
AddingwithPositiveandNegativeNumbers
Whenaddingwithpositivesandnegatives,ifthesignsarethesame,addthenumberstogetherandkeepthesign.Ifthesignsaredifferent(onepositiveandonenegative)taketheabsolutevalueofeachnumberandsubtractthelargerabsolutevalueminusthesmaller.Keepthesignofwhichevernumberhasthebiggerabsolutevalue.
SubtractingwithPositiveandNegativeNumbers
Whensubtractingwithpositivesandnegatives,turnthesubtractionexpressionintoanadditionexpressionbyusingthemethodkeep,change,change.Oncetheexpressionissetupasaddition,followthesamestepsyouwouldforaddingwithpositivesandnegatives.
MultiplyingandDividingwithPositiveandNegativeNumbers
Whenmultiplyingordividingwithpositivesandnegatives,ifthesignsarethesametheanswerwillbepositive,ifthesignsaredifferenttheanswerwillbenegative.
•Apositivenumbermultipliedordividedbyanotherpositivenumberresultsina positiveanswer.
•Apositivenumbermultipliedordividedbyanegativenumberresultsina negativeanswer.
•Anegativenumbermultipliedordividedbyanothernegativenumberresultsina positiveanswer.
• Anegativenumbermultipliedordividedbyapositivenumberresultsinanegativeanswer.
!Example:!!17!+!-!12!!! !17!+!-!12!=!5!!!!!!!!!!!!!!
!Example:!!19!+!-!27!!! 19!+!-!27!=!-!8!!!!!!!!!!!!!!!
!Example:!!*!4!+!*!16!!! !*!4!+!*!16!=!*!20!!!!!!!!!!!!!!
!Example:!!17!+!-!12!!! !17!+!-!12!=!5!!!!!!!!!!!!!!
Adding Integers
Section 2Integers and Signed Numbers
4
!Example:!!−!47! − !−21!!
−!47!− !−21!!(keep,!change,!change)!
!!!!!!!!!!!! − !47!+ !+!21 = −26!!!!!!!!!!!!!!
!Example:!!37!,!46!!
37!,!46!!(keep,!change,!change)!37!+!,!46!=!,!9!!
!!!!!!!!!!!!!
!Example:!!*!49!*!23!!
*!49!*!23!!(keep,!change,!change)!*!49!+!*!23!=!*!72!
!!!!!!!!!!!!!
!Example:!!−!47! − !−21!!
−!47!− !−21!!(keep,!change,!change)!
!!!!!!!!!!!! − !47!+ !+!21 = −26!!!!!!!!!!!!!!
Subtracting Integers
!Example:!!−16! ∙ !−4!!!!!!!! !!!!!−16! ∙ !−4 = +!64!
!Example:!!32 ∙ !−2!!!!!!!! !!!!!32 ∙ !−2 = −64!
!Example:!!−20!÷ !−4!!!!!!!! !!!!!−20!÷ !−4 = +!5!
!Example:!!−45!÷ !+5!!!!!!!! !!!!!−45!÷ !+5 = −9!
!Example:!!−16! ∙ !−4!!!!!!!! !!!!!−16! ∙ !−4 = +!64!
Multiplying and Dividing Integers
PracticeProblems1
PracticeProblems2
5
Parentheses,Exponents,Multiplication,Division,Addition,andSubtraction
Whencompletingallmathematicalexpressionsthereisanorderofoperationsthatisfollowed.Thisorderismostcommonlyreferredtoas“PEMDAS,”whichstandsforparentheses,exponents,multiplication,division,addition,andsubtraction.
• Parentheses:Anyoperationsinsideofparenthesesshouldbeperformed;irst.Iftherearetwosetsofparentheses,alwaysstartwiththeinnermostparenthesesandworkyourwayout.Next,moveontoexponents.
• Exponents:Performalloperationswithexponentsnext.Rememberthatexponentsstatehowmanytimesanumbershouldbemultipliedbyitself.Next,moveontomultiplicationanddivision.
• MultiplicationandDivision:Multiplicationanddivisionshouldbeperformedfromlefttoright.Ifdivisioncomesbeforemultiplicationinanexpression,itshouldbeperformed;irst,andviceversa.Next,moveontoadditionandsubtraction.
• AdditionandSubtraction:Additionandsubtractionshouldbeperformedfromlefttoright.Ifsubtractioncomesbeforemultiplicationinanexpression,itshouldbeperformed;irst,andviceversa.Attheendofadditionandsubtraction,yourexpressionshouldbecompleted.
PracticeProblems1
PracticeProblems2
!Example:!!16!÷ 4! ∙ !2! − 10− 7 + 5!!16!÷ 4! ∙ !2! − 10− 7 + 5!16!÷ 4! ∙ !2! − 3+ 5!16!÷ 4! ∙ !4− 3+ 5!4! ∙ !4− 3+ 5!16− 3+ 5!13+ 5!=!18!!!!!!!!
Section 3Order of Operations
6
Order of Operations
BasicTermsandDeGinitions
Inthestudyofmathematicstherearetermsthatareseenfrequently.Itisimportanttoknowthede;initionandhaveanunderstandingoftheseterms.
• Sum-theanswerthatisreachedwhenaddingtwoterms.
• Difference-theanswerthatisreachedwhensubtractingtwoterms.
• Product-theanswerthatisreachedwhenmultiplyingtwoterms.
• Quotient-theanswerthatisreachedwhendividingtwoterms.
• Variable-aletterthatisusedtorepresentanumber
• Term-referstoanumber,variable,orbothheldtogetherbymultiplicationor division.
• Factors-thenumbersmultipliedtogethertoreachaspeci;icproduct.
• Example:thefactorsof8are:1and8,2and4
• Multiples-theproductwhenaspeci;icnumberismultipliedbyaninteger.
• Example:themultipliesof8are:0,8,16,24,32,40
• Coef;icients-thenumberinfrontofavariable.Ifavariabledoesnothavea coef;icient,thecoef;icientisone.
• Example:thecoef;icientof6xis6
EvaluatingExpressions(Substitution)
Whenevaluatinganexpression,substitutethevariableintheexpressionwiththenumberassignedtoit.Ifthevariableappearsmorethanonceintheexpression,replaceiteachtime.Oncethevariablesarereplacedintheexpression,simplifybyfollowingtheorderofoperations.
PracticeProblems
Substitution
Section 4Basic Definitions and Evaluating Expressions
7
Sets
• Sets-agroupofelementsornumbers
• Elements-themembersofaset
• Thesymbol
€
∈meansanelementofaset.Thesymbol
€
∉meansnotanelementofaset.
• Example:A={1,2,3,4},4
€
∈A,5
€
∉A:WhengivensetA,4isanelementofthesetand5isnotanelementoftheset.
• EqualSets-havethesameelementsintheirsetsbutmaybewritteninadifferentorder.
• Example:{1,2,3}and{2,1,3}areequalsetsbecausetheyhavethesameelementsintheirsets.
• EquivalentSets-havethesamenumberofelementsintheirsetsbutnotalwaysthesameelements.
• Example:{1,2,3,4}and{M,A,T,H}areequivalentsetsbecausetheybothhavefourelements.
• ContinuousSet-thepatterninasetcontinueswhenasetendswiththreedots.
• Example:{2,4,6…}:Meansallevennumbersfrom2continuingtoin;inity.
• FiniteSet-asetwhoseelementscanbecounted.
• Example:{studentsattendingKellenberg}
• In;initeSet-asetwhoseelementscannotbecounted.
• Example:{allevennumbers}
• Empty/NullSet-therearenoelementsinaset.Canbewrittenas{}or
€
∅ .
• Example:{;ifthgradestudentsattendingKelleneberg}
• Predecessor-thenumberthatprecedes(comesbefore)anothernumber.
• Example:3isthepredecessorof4.
• Successor-thenumberthatcomesafteranothernumber.
• Example:4isthesuccessorof3.RealNumbers
Realnumbersincludeallrationalanirrationalnumbers.
RationalNumbers
Rationalnumbersconsistof:
• NaturalNumbers-Startwithoneandcontinuetopositivein;inity{1,2,3…}.
• WholeNumbers-Startwithzeroandcontinuetopositivein;inity{0,1,2…}.
• Integers-wholenumbersandtheiropposites,continuingtobothnegativeandpositivein;inity{…-2,-1,0,1,2…}.
• TerminatingDecimals-decimalsthatend.
• Example:½=0.5
• RepeatingDecimals-decimalsthatdonotendbutcontinuouslyrepeat.
• Example:
Section 5Sets
8
€
13 = 0.3
IrrationalNumbers
Irrationalnumbersarenumbersthatdonot;itthecriteriaofrationalnumbers.Piisanirrationalnumber.Squarerootsthatdonothaveaperfectsquarearealsoirrational.
• Example:
€
π = 3.14159265359...
• Example:
€
7 = 2.64575131106...
PracticeProblems9
Closure
Asetisclosed(notopen)underaspeci;icoperationifallanswerstotheoperationareinthesetofgivennumbers.Setscanbeclosedundercertainoperationsandnotclosedunderotheroperations.
**Numbersinasetcanbeadded,subtracted,multiplied,ordividedbythemselves.**
PracticeProblems
Closure
Section 6Closure
10
AdditionTermsinVerbalSentences
Termsusedtoexpressadditioninaverbalsentenceare:sum,plus,morethan,inadditionto,andexceeds.
• Example:Anumber,n,exceededby12iswrittenas:n+12
SubtractionTermsinVerbalSentences
Termsusedtoexpresssubtractioninverbalsentencesare:difference,minus,subtractedfrom,less,andlessthan.Whenwritingexpressionsusinglessthanandsubtractedfromthe;irsttermcomessecondandthesecondtermcomes;irst.
• Example:12minusanumber,n,iswrittenas:12–n
• Example:12lessthananumber,n,iswrittenas:n–12
MultiplicationTermsinVerbalSentences
Termsusedtoexpressmultiplicationinverbalsentencesare:product,multipliedby,andtimes.Twiceanumbermeanstwotimesanumber.
• Example:Theproductof12andanumber,n,iswrittenas:12n
• Example:Twiceanumber,n,iswrittenas:2n
DivisionTermsinVerbalSentences
Termsusedtoexpressdivisioninverbalsentencesare:quotient,anddividedby.
• Example:12dividedbyanumber,n,iswrittenas:
€
12n or12÷ n
OtherCommonTermsinVerbalSentences
• Ismeansequals
• Ofmeansmultiplication
• Halfmeanstomultiplyby½ordivideby2
PracticeProblems
Section 7Writing Verbal Statements
11
AdditionProperties
• CommutativePropertyofAddition-youcanaddnumbersinanyorder.
• Example:4+5=5+4
• AssociativePropertyofAddition-youcangroupnumbersinanyorderwhenadding.
• Example:(4+5)+6=4+(5+6)
• AdditionPropertyofZero(AdditiveIdentity)-whenanynumberisaddedtozero,thenumberstaysthesame.
• Example:4+0=4
• AdditionPropertyofOpposites(AdditiveInverse)-whenoppositesareaddedtogether,theyarealwayszero.
• Example:-4+4=0
MultiplicationProperties
• CommutativePropertyofMultiplication-youcanmultiplynumbersinanyorder.
• Example:4x5=5x4
• AssociativePropertyofMultiplication-youcangroupnumbersinanyorderwhenmultiplying.
• Example:(4x5)x6=4x(5x6)
• MultiplicationPropertyofZero-whenzeroismultipliedbyanynumber,theanswerisalwayszero.
• Example:4x0=0
• MultiplicationPropertyofOne(MultiplicativeIdentity)-whenanynumberismultipliedbyone,thenumberstaysthesame.
• Example:4x1=4
• MultiplicationPropertyofReciprocals(MultiplicativeInverse)-whenanynumberismultipliedbyitsreciprocal,theanswerisalwaysone.
• Example:2x½=1
• DistributiveProperty-whenanumberisoutsideapairofparenthesesitisdistributedtoalltermsinsidetheparenthesesthroughmultiplication.
• Example:4(x+4)=4(x)+4(4)=4x+16
PropertiesofEqualities
• AdditionPropertyofEquality-thesamenumbercanbeaddedtobothsidesofanequation.
• Example:Ifa=b,thena+c=b+c
• SubtractionPropertyofEquality-thesamenumbercanbesubtractedfrombothsideofanequation.
• Example:Ifa=b,thena-c=b-c
Section 8Properties of Equality
12
• MultiplicationPropertyofEquality-thesamenumbercanbemultipliedonbothsideofanequation.
• Example:Ifa=b,thenaxc=bxc
• DivisionPropertyofEquality-thesamenumbercanbedividedonbothsidesofaequation.
• Example:Ifa=b,thena/c=b/c
• Re;lexiveProperty-anynumberisequaltoitself.
• Example:4=4
• SymmetricProperty-anequationcanbewritteninanyorder.
• Example:x=4and4=xarethesame
• TransitiveProperty-ifa=bandb=c,thena=c
• Example:If
€
12
=24 and
€
24
=36 then
€
12
=36
• SubstitutionProperty-youcansubstitutequantitiesforoneanotherinanexpression.
• Example:ifa=6,then4+a=4+6
PracticeProblems
13
CombiningLikeTerms
Termsarelikeoneanotheriftheyhavethesamevariableandthesameexponent.Whenaddingorsubtractingliketerms,addorsubtractthecoef;icientsandkeepthevariableandexponentthesame.
PracticeProblems1
PracticeProblems2
Combining Like Terms
Section 9Like Terms
14
SOLVING EQUATIONS
Chapter 2
2.1 One-Step Equations2.2 Two-Step Equations2.3 Parentheses and Variables on Both Sides2.4 Word Problems2.5 Working with Formulas2.6 Solving and Graphing Inequalities2.7 Absolute Value Equations2.8 Absolute Value Inequalities
InverseOperations
• AdditionandSubtractionareinverseoperations
• MultiplicationandDivisionareinverseoperations
**FractionalCoefGicients**
-Usethereciprocalastheinverse.
PracticeProblems
!Example:!!!Solve:!!x!+!6!=!14!!! x!+!6!=!14!! !!!2!!6!!!!!2!6!! !!!!!!x!!=!!8!!Check:!! x!+!6!=!14!! 8!+!6!=!14!! !14!=!14!✓!!!
!Example:!!!Solve:!!x!–!13!=!27!!! x!–!13!!!=!27!! !!!!+13!!!+!13!! !!!!!!!!!!x!!=!40!!!Check:!
x!–!13!!!=!27!!!!!!!!!!!!!40!–!13!=!27!!!!!!!! !!!27!=!27!✓!! !!
!Example:!!!Solve:!!4x!=!24!!! 4x!=!24!! !4!!!!!!!4!!! !!x!=!6!!Check:!! 4x!=!24!!!!!!!!!!!!4(6)!=!24!!!!!!!!!!!!24!=!24!✓!!
!Example:!!!Solve:!!x!=!24!! !!!!!!!!!!!!!!!!!!!!6!!!!!!!!!
6!∙!!x!!=!24!! !!!!!!6!!!!!!!!!! !!x!=!144!!Check:!!!!!!!!!!!!!!x!!=!24!!!!!!!!!!!!!!6!!!!!!!!!!!!!!144!=!24!!!!!!!!!!!!!6!!!!!!!!!!!!!!!!!!24!=!24!✓!!!!!!!!!!
!Example:!!!Solve:!!x!+!6!=!14!!! x!+!6!=!14!! !!!2!!6!!!!!2!6!! !!!!!!x!!=!!8!!Check:!! x!+!6!=!14!! 8!+!6!=!14!! !14!=!14!✓!!!
Addition Equation
Section 1One-Step Equations
16
!Example:!!!Solve:!!!! ! = 4!!!! !
! ∙!! ! = 4 ∙ !!!
! !! x!=!!"! !=!10!!Check:!!!!!!!!!!!!!!!!!!! ! = 4!!
!!!! 10 = 4!!!!!"! = 4!!
!!!!!!!!!!!!!!!!4!=!4!✓!!!!!!!!!!
ToSolve:
-Dotheinverseoftheoperationintheequationonbothsidesoftheequal sign.
-Checkyouranswerbackintotheoriginalequation.
-Solveeachsideindependently.
SolvingTwo-StepEquations
PracticeProblems
!Example:!!!Solve:!!!! + 9 = 12!!! !
! + 9 = 12!! !!!!-!9!!!!!!!-!9!!!!!!!!!!!!!!!2 ∙ !!! = 3 ∙ 2!! !!!!!!!!x!=!6!!!!!!!!!!!!!!!!Check:!!!!!!!!!!!!!!!! + 9 = 12!!!!!!!!!!!!!!!!! + 9 = 12!!! 3!+!9!=!12!!
!!!!12!=!12!✓!!!!!!!!!!
!Example:!!!Solve:!!4! − 7 = 9!!! 4! − 7 = 9!! !!!!!!+!7! !!+!7!! !!4x!=!16!! !!!4!!!!!!!4!! !!!!!x!=!4!Check:!!!!!!!!!!!!!!4! − 7 = 9!!!!!!!!!!!!!4(4)!–!7!=!9!! 16!–!7!=!9!
!!!!9!=!9!✓!!!!!!!!!!
!Example:!!!Solve:!!!! + 9 = 12!!! !
! + 9 = 12!! !!!!-!9!!!!!!!-!9!!!!!!!!!!!!!!!2 ∙ !!! = 3 ∙ 2!! !!!!!!!!x!=!6!!!!!!!!!!!!!!!!Check:!!!!!!!!!!!!!!!! + 9 = 12!!!!!!!!!!!!!!!!! + 9 = 12!!! 3!+!9!=!12!!
!!!!12!=!12!✓!!!!!!!!!!
Solving 2-Step Equations
Section 2Two-Step Equations
17
ToSolve:
-Dotheinverseofadditionandsubtraction;irst.
-Thentheinverseofmultiplicationanddivision.
-Check.
EquationswithParenthesesandVariablesonBothSides
FractionBarsinEquations
PracticeProblems
!Example:!!!Solve:!!– !4(!!– 2) = 16!!! – !4 !!– 2 = 16!! !!!–!4x!+!8!=!16!! !!!!!!!!!!!!!4!8!!!!4!8!! !!!–!4x!=!!8!!!!!!!! !!!!–4!!!!!–4!! !!!!!!!x!=!–!2!Check:!!!!!!!!!!!!– 4(! − 2) = 16!!!!!!!!!!!!–!4(–2!–!2)!=!16!!!!!!!!!!!!!!!–!4(–!4)!=!16!! !!!!16!=!16!✓!!!!!!!!!!
!Example:!!!Solve:!!2x− 7 = 4x+ 13!!! 2x− 7 = 4x+ 13!!!!!!!!!!!!-!2x! !!!-!2x!!!!!!!! !!!!!!!-!7!=!2x!+!13!! !!!!-!13!!!!!!!!!!!-!!13!!!!!!!!!!!!!!!!!!!-!20!=!!2x!!!!!!!!! !!!!!!!2!!!!!!!!!2!! !!!!!!-10!=!!x!Check:!!!!!!!!!!!!2x− 7 = 4x+ 13!!!!!!2(-10)!-!7!=!4!(-10)!+!13!!!!!!!!!!!!!!!-!20!-!7=!-!40+13!! !!!!-!27!=!-!27!✓!!!!!!!!!!
!Example:!!!Solve:!!– !4(!!– 2) = 16!!! – !4 !!– 2 = 16!! !!!–!4x!+!8!=!16!! !!!!!!!!!!!!!4!8!!!!4!8!! !!!–!4x!=!!8!!!!!!!! !!!!–4!!!!!–4!! !!!!!!!x!=!–!2!Check:!!!!!!!!!!!!– 4(! − 2) = 16!!!!!!!!!!!!–!4(–2!–!2)!=!16!!!!!!!!!!!!!!!–!4(–!4)!=!16!! !!!!16!=!16!✓!!!!!!!!!!
Parentheses Example
Section 3Parentheses and Variables on Both Sides
18
ToSolve:
-Distributeanynumbersoutsideparenthesestoalltermsinside.
-Combineanyliketerms.
-Isolatevariablesononesideoftheequationbyusinginverseoperationsof additionandsubtractiontobringthemovertotheotherside.
-Isolateallothernumbersontheothersidebyusinginverseoperationsof additionandsubtractiontobringthemovertotheotherside.
-Useinverseoperationstosolveforthevariable.
-Check.
Parentheses and Variables on Both Sides
ToSolve:
-UndoanyadditionorsubtractionNOTincludedinthefraction.
-Undothedivisionofthefraction.
-Finishlikearegularequation.
-Check.
Fraction Bar in Equation
WordProblems
PracticeProblems
ToSolve:
-SetupaLetStatementtorepresentthebasicunknown.
-Everythingelseisrepresentedintermsofthatvariable.
-Writeanequation.
-Solve.
Section 4Word Problems
19
Word Problems
ReplacingVariablesinaFormula:
-Pluginthegivenvaluesintothecorrectformula.
-Solveforthemissingvariable.
WritingaFormulawithGivenVariables:
-Usethevariablesinthewordproblemtosetupaformula.
SolvinginTermsofaVariable:
-Isolatethevariableyouare solvingintermsofbyusing inverseoperationstogetthe desiredvariablealone.
PracticeProblems
!Example:!!!A!=!LW,!Find!W!when!A=!36cm2!and!L=!9cm!! !! ! A!=!LW!! !!!!!!!!!!!!36!=!9L!! ! 9!!!!!!!9!! ! 4!cm!=!L!!!!!!!!!!
Section 5Working with Formulas
20
!Example:!!!The!distance,!d,!is!equal!to!the!rate,!r,!times!the!time,!t.!!! ! ! d!=!rt!!!!!!!!!! !
Example:!!!Solve!in!terms!of!y.!!! ! 6y!+!x!=!!z!! ! !!!!!!9!x!!!!9!x!! ! !!6y!=!x!–!z!! ! !!!6!!!!!!!!!6!! ! !!!y!=!x!–!z!! ! !!!!!!!!!!!!6!!!!!!!!!!
GraphingonaNumberLine:
• SeparatePoints:Individualpointsonanumberline.
• Ex:Wholenumbersbetween1and5.
• ContinuousPoints:Notjustindividualpoints,butallrealnumbersinbetween.
• <and>haveanopenpointonthegraph.
• ≤and≥haveaclosedpointonthegraph.
• Ex:Realnumbersgreaterthan7.
• Ex:Realnumbersbetween2and5.
• CompoundInequalities:twoinequalitiesthatcometogethertoformoneinequality.
• Ex:Realnumbersgreaterthan2butlessthanorequalto5.
SetNotation:
• Asymbolicwayofwritingananswer.Thinkofitasamathsentence.
• Ex:“thesetofallnumbersgreaterthan2”becomes{x:x>2}
• Ex:“thesetofrealnumbersbetween1and5”becomes{x:1<x<5}
• Ex:“thesetofrealnumbersgreaterthanorequalto-3andlessthan4”becomes{x:-3≤x<4}
SolvingInequalities:
-Useinverseoperationstosolveforthevariable. **WhenmultiplyingordividingbyaNEGATIVENUMBER,youmustchange theinequalitysign.** So<to>or≤to≥andviceversa. -Ifyourinequalityendsupwiththeconstantcomingbeforetheinequalitysign, reversetheinequalitysothatitstartswiththevariable. Ex.Change7>xtox<7 -Graphyourinequality. -Checkyouranswer. -Writeyour;inalanswerinsetnotation.
Section 6Solving and Graphing Inequalities
21
https://sites.google.com/a/kellenberg.org/mrs-farrell/home
Solving Inequalities 1
Solving Inequalities 2
PracticeProblems1
PracticeProblems2
22
AbsoluteValueEquations
AbsoluteValue:anumber’sdistancefromzero.
Ex.:|-8|=8and|+8|=8
PracticeProblems
ToSolve:
-Isolatetheabsolutevalueexpressionononesideoftheequation. **YoumustgetridofEVERYTHINGELSE** -Splittheequationintotwoseparateequations,droppingtheabsolutevalue bars. -FirstEquation:Droptheabsolutevaluebars.Leavetherestofthe equationalone. -SecondEquation:Droptheabsolutevaluebars.NEGATEthe OTHERside(changethesigns). -Solveeachequationindependently. -TwoChecks -CheckeachoftheanswersintotheORIGINALabsolutevalue equation. -FinalanswerinSetNotation. -SmallerNumbergoes;irst.
Section 7Absolute Value Equations
23
Absolute Value Equation 1
Absolute Value Equation 2
AbsoluteValueInequalities
PracticeProblems
ToSolve:
-Isolatetheabsolutevalueexpressionononesideoftheinequality. **YoumustgetridofEVERYTHINGELSE** **Remembertherulesformultiplyingordividingbyanegative number** -Splittheequationintotwoseparateinequalities,droppingtheabsolute valuebars. -FirstInequality:Droptheabsolutevaluebars.Leavetherestof theinequalityalone. -SecondInequality:Droptheabsolutevaluebars.FLIPthe inequalitysign.NEGATEtheentireOTHERside.(changeall ofthesigns) -Solveeachinequalityindependently. -Graphtheinequalities. -Check. **IftheanswersfaceAWAYfromeachother,2checksneeded.This happenswithGREATERTHANinequalities.** **IftheanswersfaceTOWARDSeachother,only1checkneeded. ThishappenswithLESSTHANinequalities.Youneeda compoundinequalityinyoursetnotationhere. -FinalanswerinSetNotation.
Section 8Absolute Value Inequalities
24
Absolute Value Inequality 1
Absolute Value Inequality 2
Whentwoinequalitiesonagraphfacetowardseachother,acompoundinequalitymustbewritten.
Towriteacompoundinequality,putyouranswersinorderfromleasttogreatestwithavariableinbetweenthem.Allsignsshouldbelessthanor
lessthanorequalto.
WORD PROBLEMS
Chapter 3
3.1 Consecutive Integer Problems3.2 Money-Value Problems3.3 Investment Problems3.4 Motion Problems3.5 Perimeter Word Problems3.6 Percent Mixture Problems
ConsecutiveIntegers:
Therearethreetypesofconsecutiveintegers:
Everyproblemwillstatehowmanyandwhattypeofconsecutiveintegerstouse.
TherearetwotypesofLetstatements:
PracticeProblems1
PracticeProblems2
1)ConsecutiveIntegers(i.e.3,4,5,6)
2)ConsecutiveEvenIntegers(i.e.4,6,8,10)
3)ConsecutiveOddIntegers(i.e.3,5,7,9)
Section 1Consecutive Integer Problems
26
Forconsecutiveintegers:
Letx=1stconsecutiveinteger
Letx+1=2ndconsecutiveinteger
Andsoon,adding1toeach.
Forconsecutiveevenoroddintegers:
Letx=1stconsecutiveeven(orodd)integer
Letx+2=2ndconsecutiveeven(orodd)integer
Andsoon,adding2toeach.
Note:Evenandoddnumbersareboth2apart.
Tosolve:
-Notehowmanyandwhattypeofconsecutiveintegersinordertowrite theletstatements.
-Writeanequationwhichfollowsthewords.
-Solveandanswerthequestionintheproblem.Makesureyouranswer makessense.
Consecutive Integer Problem
1
Consecutive Integer Problem
2 (Even/Odd)
MONEY-VALUECHART:
To;indthetotalvalueofanumberofacertainitem,thefollowingformulaisused:
PracticeProblems
Kind or Type Value of One Item
Number of Items
Total Value of Item
Section 2Money-Value Problems
27
Tosolve:
-WriteLetstatementsforeachitem(thesewilldescribehowmanyofeach item).
-Puttheinformationinthechart(theletstatementswillbeusedforthe numbercolumn).Thelastcolumnwillbetheproductofthevalueand numbercolumns(usetheformula).
-Writetheequationbyaddingthelastcolumnforeachitemandsetit equaltothetotalmoneygivenintheproblem.
-Solvetheequationandchecktoseethatthetotalvaluesadduptothe totalgiven.
(valueofoneitem)x(numberofthatitem)=(totalvalueoftheitem)
Money-Value Problems 1
Money-Value Problem 2
INVESTMENTPROBLEMCHART:
• Principal–theamountbeinginvestedatacertainrate
• Rate–thepercentusedfortheinvestment(principal)
• Income–themoneyearnedontheinvestment
Tosolveinvestmentproblemsusethefollowingformula:
PracticeProblems1
PracticeProblems2
Type Principal Rate Income
Section 3Investment Problems
28
PrincipalxRate=Income
Tosolve:
-Writeletstatementsforeachprincipalbeinginvested.
-Puttheinformationinthechart.Thelastcolumnwillbetheproductof theprincipalandtherate.
-Writetheequationbyaddingtheincomesorfollowingthewordsofthe problem.
Note:totalannualincomeisthesumforalltheincomesinthe chart.
-Solvetheequationandchecktoseeiftheincomesmakesense.
-Answerthequestionintheproblem.
Investment Problem 1
Investment Problem 2
MOTIONPROBLEMCHART:
Tosolvemotionproblemsusethefollowingformulatogetlastcolumn:
PracticeProblems
Kind or Type Rate or Speed of One Time Traveled Distance of
One
Section 4Motion Problems
29
(rateofone)x(timetraveled)=(distancetraveled)
Therearethreedifferentsetupsforthe;ivemotionscenarios:
ToSolve:
-Writealetstatement(s)tode;inetheunknown(thisiseithertherateor thetime).
-Puttheinformationinthechart.
-Determinewhichtypeofequationtouse.Usethedatafromthelast columnintheequation.
-Solvetheequationandchecktoseethatthedistancesmakesenseinthe problem.
-Answerthequestionintheproblem.
Motion Problem 1
Motion Problem 2
Motion Problem 3
AdditionSetup:
Usedwhenthesumofthetwodistances
isgiven.
SubtractionSetup:
Usedwhenthedifferencebetweenthetwodistancesis
given.
EqualSetup:
Usedinroundtripandcatch-upproblems.
PerimeterWordProblems:
Forperimeterproblemsusetheformulas:
.
PracticeProblems
2L+2W=perimeterofrectangle
4s=perimeterofasquare
a+b+c=perimeteroftriangle
Section 5Perimeter Word Problems
30
Tosolve:
-Readtheproblemtodeterminehowmany;iguresareintheproblemand ifmorethanone,howtheycompare.
-Writeletstatementsforlengthandwidthoforiginalandanyother;igure.
-Ifa;igurechangesdimensions,setupanoriginalandanew
-Theequationwillfollowthewordsoftheproblemusingtheformulas.
-Solveandanswerthequestionintheproblem.
Perimeter-Triangle
Perimeter-Rectangle
MixtureProblemsChart:
To;indthetotalofeachtype,usethefollowingformula:
Section 6Percent Mixture Problems
31
Type Number of Units Price per Unit Total
Type 1
Type 2
Mixture
(#ofunits)x($perunit)=(Total)
The#ofunitscolumnshouldadddowntototalthe#ofunitsinthemixture.
The$perunitofthemixtureshouldbebetweenthe$perunitofthetwotypes.
ToSolve:
-WriteLetStatementforeachitem.
-FillintheChart.
-MultiplyAcrosstogettheTotalColumn.
-WriteanequationusingtheTotalColumn.
Type1Total+Type2Total=MixtureTotal
-Solvetheequation.
-Check.
-Answerthequestionintheproblem
Mixture Problem
PercentMixtureProblems:
To;indthetotalofeachtype,usethefollowingformula:
PracticeProblems32
Type Number of Units Solution
Percent Pure Solution Total
Type 1
Type 2
Mixture
**Remember:PureSolutionis100%whilePureWateris0%**
(#ofunits)x(%perunit)=(Total)
The#ofunitscolumnshouldadddowntototalthe#ofunitsinthemixture.
The%perunitofthemixtureshouldbebetweenthe%perunitofthetwotypes.
ToSolve:
-WriteLetStatementforeachitem.
-FillintheChart.
-MultiplyAcrosstogettheTotalColumn.
-WriteanequationusingtheTotalColumn.
Type1Total+Type2Total=MixtureTotal
-Solvetheequation.
-Check.
-Answerthequestionintheproblem.
Percent-Mixture Problem 1
Percent-Mixture Problem 2
FRACTIONAL AND DECIMAL COEFFICIENTS
Chapter 4
4.1 Ratio4.2 Proportion4.3 Lever and Pulley Problems 4.4 Variation4.5 Solving Equations with Fractional Coefficients4.6 Solving Equations with Decimal Coefficients4.7 Work Word Problems
Ratios
Aratioisarelationshipoftwonumbersbydivision.Therearethreewaysthatratioscanbewritten:withacolon,usingthewordto,orasafraction.Ratiosareexpressedusingthesameunitandalwaysexpressedinsimplestterms.Denominatorsofoneremainintheratio.
RatioWordProblems
Whenexpressingratioinawordproblem,usetheratioandavariabletoexpresstheletstatements.
Rates
Arateisarelationshipoftwonumbersbydivision.Unlikeratios,rateshavetwodifferentunits.Ratesareexpressedinsimplesttermsthatusuallyhaveadenominatorofone.Ifthedenominatorisone,theoneisomittedandtheunitsarewrittenasasinglerate.
Example:45milesinonehouriswrittenas:45milesperhour.
PracticeProblems1
PracticeProblems2
Section 1Ratio
34
Ratio Word Problem
Rate Word Problem
Example:Inaclass,thereare15boysand12girls.Theratioofboystogirlsis15:12,whichsimpli;iesto5:4.
Proportions
Aproportionconsistsoftworatiosthatareequaltooneanother.
SolvingforaMissingVariableinaProportion
Tosolveforamissingvariableinaproportion,usecross-multiplication.Solvetheequationto;indthemissingvariable.
ProportionWordProblems
Whensettingupproportionwordproblemsmakesuretheunitsoneachsideoftheequalsignaresetupthesameway.Cross-multiplyproportionwordproblemstosolve.
FindingtheOriginalFractionWordProblems
Usingonevariablesetupanoriginalfractiontorepresentthenumeratoranddenominatorofthefraction.Ifthenumeratorand/ordenominatorarechangedsetupanewfraction.Cross-multiplytosolve.Forthe;inalanswerplugbackintotheoriginalfractionbutdonotsimplifytheanswer.
PracticeProblems1
PracticeProblems2
PracticeProblems3
Ratiosthatmakeupaproportioncanbeprovedequivalenttoeachotherinoneofthefollowingways:
1)Whencross-multiplyingequivalentfractions,theproductofthemeansandtheproductoftheextremes(thetwodiagonals)willequaleachother.
2)Whenputtingbothfractionsinsimplestterms,theyareequaltoeachother.
Section 2Proportion
35
Proportion 1 Proportion 2
Proportion with a Missing Variable
Proportion Word Problem
Finding Original Fraction
LeverWordProblems
Leversareusedinmanydifferentways.Aleverisusuallyusedtoassistinliftingheavyobjects.Aleverismadeupofabarthatisattachedtoafulcrum.Seesawsareanexampleoflevers.Theweightoneachsideofthelever,andthedistancethatweightisfromthefulcrumeffectshowtheleverworks.Inorderforalevertoworkproperlytheweightanddistanceononesidemustbeequaltotheweightanddistanceontheotherside.
PulleyWordProblems
Apulleyisasystemoftwowheelsthatworkinconjunctionwitheachother.Acordrunsbetweentothetwowheels.Elevatorsareanexampleofsomethingthatrunsonapulleysystem.Thediameterofthewheeloneachsideofthepulley,andthespeedatwhichtheyturneffectshowthepulleyworks.Inorderforapulleytoworkproperlythediameterandspeedononesidemustbeequaltothediameterandspeedontheotherside.
PracticeProblems
LeverFormula:(weight1)x(distance1)=(weight2)x(distance2)
Section 3Lever and Pulley Problems
36
PulleyFormula:(speed1)x(diameter1)=(speed2)x(diameter2)
Lever Pulley
DirectVariation
Directvariationoccurswhentwovariableshaveaconstantratio.Whendirectvariationoccursasonevariableincreasessodoestheother.
InverseVariation
Inversevariationoccursasonevariableincreasestheotherdecreases.
PracticeProblems
Setupasaproportion(x/y=x/y)
Section 4Variation
37
Setupasanequation(xy=xy)
**ThinkLeverandPulleyProblems**
Direct Variation
Inverse Variation
EquationswithFractionalCoefGicients
Ifthereisonefractiononeachsideofanequationusecrossmultiplicationtosolve.Whenthereismorethanonefractiononeachsideoftheequationyoumustuseleastcommonmultiplestoarriveattheanswer.
PracticeProblems1
PracticeProblems2
ToSolve:
-Findtheleastcommonmultipleofallthedenominators.
-Multiplytheentireequationbytheleastcommonmultiple.
-Cross-simplifyeachfractionandleastcommonmultipleinorderto eliminatethedenominators.
-Solvetheequationandcheck.
Section 5Solving Equations with Fractional Coefficients
38
Fractional Coefficient Equation
Fractional Coefficient Word
Problem
EquationswithDecimalCoefGicients
Whensolvingequationswithdecimalsuseleastcommonmultiplestoarriveattheanswer.
WordProblemswithDecimalCoefGicients
Anydecimalwordproblemthatconsistsofapercentrequiresyoutoturnthepercentintoanumber.Sinceapercentisoutof100,divideapercentby100(movethedecimalpointtoplacestotheleft)tomakeitanumber.
PracticeProblems1
PracticeProblems2
ToSolve:
-Findtheleastcommonmultipleofthedecimals.Thisisdeterminedby choosingthenumberwiththemostplacesafterthedecimalpoint.
-Determinehowmanyplacesthedecimalpointneedstobemovedto makeitawholenumber.Eachtimeyoumovethedecimalpointtothe rightyouaremultiplyingbyten. -Multiplytheentireequationbytheleastcommonmultiple(alwaysa multipleof10),thereforeeliminatingalldecimals.
-Solvetheequationandcheck.
Section 6Solving Equations with Decimal Coefficients
39
Decimal Coefficient Equation
Decimal Coefficient Word
Problem
WORKWORDPROBLEMCHART:
PracticeProblems
Person Rate (1/# alone)
# Hours/Minutes Together
Part of Job
Person 1
Person 2
Section 7Work Word Problems
40
**Rateisalwayswrittenas1/#alone.Asin“1jobcompletedper3hours.”**
**The3rdcolumnisALWAYSthecombinedtimeandmustbethesameforeachperson.**
ToSolve:
-Writealetstatement.
-FillintheChart,multiplyingacrosstogetthePartofJobcolumn.
-Setupanequationusingthefollowingformula:
PartofJob1+PartofJob2=1
-Solve.
-Check.
-Answerthequestionintheproblem.
Work Word Problem
SYSTEMS OF EQUATIONS
Chapter 5
5.1 Addition Method5.2 Substitution Method5.3 Business Word Problems5.4 Two-Variable Word Problems
**PossibleOutcomes**
PracticeProblems
ToSolve:
-Putbothequationsintheform“x+y=#”.
-Getthecoef;icientsofONEvariabletobeopposites.
-Multiplyoneorbothequationstoreachopposites.
-Onceyouhaveopposites,ADDthetwoequationstogetherbycombining liketerms.
-Thisshouldeliminateoneofyourvariablesandleaveyouwitha singlevariableequation.
-Solvefortheonevariableyouhaveleft.
-Substitutethisvalueintoeitheroriginalequationtosolvefor2ndvariable.
-Checkbothvariablesintobothequations.
Section 1Addition Method
42
1.Onesolution:theanswerwillbeasinglepoint.
2. Nosolution(inconsistent):theequationsareparallellines.Thelineswillnevercrosseachothersothereisnoanswersincetheyhavenopointsincommon.
-Answersuchas0=5
3. InGinitesolutions(Dependent):theequationsarethesameline.Thelineswillhaveanin;initenumberofsolutionsbecauseeverypointthatisononelinewillalsobeonthesecondline.
-Answersuchas0=0
Addition Method 1
Addition Method 2
Addition Method-
Inconsistent
Addition Method-
Dependent
PracticeProblems
ToSolve:
-Isolateonevariableononesideoftheequation.**Doesnotmatterwhichequationorvariableyouisolate**
-ex:x=ory=
-SubstituteinthevalueofthatvariableintotheOTHERequation.
-Solvetheequation.
-Plugthevalueintoeitherequationandsolvefortheothervariable.
-Checkbothvariablesintobothequations.
Section 2Substitution Method
43
**Rememberthereare3possibleoutcomes**
Substitution Method-Easy
Substitution Method-Harder
Substitution Method-
Inconsistent
PracticeProblems
ToSolve:
-LetStatements.(1foreachvariable)
-Setuptwoequations.
-Solveusingeithertheadditionmethodorthesubstitutionmethod.
-Checkbothvariablesinbothequations.
Section 3Business Word Problems
44
Business Problem 1
Business Problem 2
PracticeProblems1
PracticeProblems2
ToSolve:
-LetStatements.(oneforeachvariable)
-Setup2equations.
-Solveusingeithertheadditionmethodorthesubstitutionmethod.
-Checkbothvariablesintobothequations.
Section 4Two-Variable Word Problems
45
Two-Variable Age Word Problem
Two-Variable Word Problem
GRAPHINGChapter 6
6.1 Plotting Points, Basics6.2 Area6.3 Slope6.4 Finding the Equation of a Line6.5 Slope-Intercept Method of Graphing6.6 X- and Y-Intercept Method6.7 Graphing Systems of Equations6.8 Graphing Inequalities6.9 Graphing Systems of Inequalities
GraphingPoints
Onacoordinateaxis,allpointscanbegraphedasanorderedpair(x,y)wherexisthehorizontalvalueandyistheverticalvalue.Thecenterofthegraphistheintersectionofthexandyaxisandiscalledtheorigin(0,0).
PracticeProblems1
SolutionstoaLine
Tocheckifapointisasolutiontothegivenline,pluginthevalueforxandthevaluefory.Iftheequationchecksout,thepointfallsontheline,andtherefore,isasolution.Ifthepointdoesnotcheckout,itisnotontheline,andtherefore,notasolution.
PracticeProblems2
Section 1Plotting Points, Basics
47
Example: y = 2x - 4, (6, 8) 8 = 2(6) - 4 8=12 - 4 8 = 8 ✔️ (6,8) is a solution for the line y = 2x - 4
Example: 2y = 3x - 5, (1, -3) 2(-3)= 3(1) - 5 -6 = 3 - 5 -6 = -2 ❌ (1, -3) is not a solution for the line 2y = 3x - 5
Example: plot the point (4,5).
AreaofShapes:
PracticeProblems
Section 2Area
48
To;indtheareaofashapeonacoordinateplane:
-Plotthepoints.
-Determinetheareaformulaforthegivenshape.
-Pluginthegivenvalues.
-Solve.
Example:
Theslopeofalineis:
PracticeProblems1
PracticeProblems2
Section 3Slope
49
!"#$%&!!"!!− !""#$%&'()!!"#$%&!"#$%&!!"!!− !""#$%&'()!!"#$%& !!!"!!
∆!∆!!
To;indtheslopebetween2pointsusetheslopeformula:
! = !!! − !!!! − !! !
To;indtheslopeofanexistingline:
-Find2pointsonthelineandcountupordownfromthe;irstpointtothe secondpoint.Placethatnumberoverthedistanceyoumoveleftorright fromthe;irsttothesecondpoint.Determineifyourslopeispositiveor negative.
• Positiveslopesincreasefromlefttoright.
• Negativeslopesdecreasefromlefttoright.
Example: Find the slope of the line passing through the points (3,4) and (−1, 3).
m = y₂ − y₁ x₂ − x₁ m = 3 − 4 = −1 = 1 −1 −3 −4 4
Example: Graph y = 4 Every point on the line y = 4 has a y-coordinate of 4.
Example: Graph x = −2 Every point on the line x = −2 has an x-coordinate of −2.
Example: Graph y = 4 Every point on the line y = 4 has a y-coordinate of 4. Horizontal Lines
• Horizontallineshaveaslopeof0.
• Verticalslopeshavenoslope(unde;ined).
• Parallellineshavethesameslope.
• Perpendicularlineshaveslopesthatarenegativereciprocalsofeachother.
FindingtheEquationofaLine:
PracticeProblems1
PracticeProblems2PracticeProblems3
To;indtheequationofalinegivenaslopeandpoint:
-Pluginm,xandyintotheequationofaline.
-Solveforb.
-Writetheequationofaline;illingintheslopeandy-intercept.
Section 4Finding the Equation of a Line
50
To;indtheequationofalinegivenalineandapoint:
-Determinetheslopeofthelinegiven.
-Isthenewlineparallelorperpendiculartothegivenline?
-Parallel:Usethesameslope.
-Perpendicular:Usethenegativereciprocal.
-Pluginyournewm,xandyintotheequationofaline.
-Solveforb.
-Writetheequationofaline;illingintheslopeandy-intercept.
To;indtheequationofalinegivenaslopeandy-intercept:
-Pluginm(slope)andb(y-intercept)intotheequationofaline.
Finding the Equation of a Line Given a Parallel Line
Finding the Equation of a Line
Given a Perpendicular Line
Example: Write the equation of a line that has a slope of −6 and a y-intercept of 4. The equation of a line is y = mx + b m is the slope, b is the y-intercept Plug in the slope and y-intercept into the equation of a line:
y = mx + b ➡️ y = −6x + 4
Answer: y = −6x + 4
Example: Write the equation of a line that has a slope of 2 and passing through the point (6, −4).
1) Plug slope and point into the equation of a line. y = mx + b
-4 = 2(6) + b -4 = 12 + b -12 -12 -16 = b 2) Plug slope and y-intercept into the equation of a line.
y = mx + b ➡️ y = 2x - 16
Answer: y = 2x - 16
PracticeProblems4
To;indtheequationofalinegiventwopoints:
-Determinetheslopeofthelinegivenusingtheslopeformula.
-Pluginmandthexandy-valuesofONEofthepointsintotheequationof aline.
-Solveforb.
-Writetheequationofaline;illingintheslopeandy-intercept.
51
Finding the Equation of a
Line Given Two Points
Slope-InterceptFormofaLine
PracticeProblems1
PracticeProblems2
Alllinescanbewrittenasy=mx+b
Whentheequationissolvedfory,thenthex-coef;icientistheslopeofthelineandtheconstantisthey-intercept.
Section 5Slope-Intercept Method of Graphing
52
Example:
Example: Find the slope and y-intercept the line: 3x + 2y = 8 - 3x - 3x 2y = 8 -3x 2 2 y = 4 - 3x 2 The slope is -3/2 and the y-intercept is (0,4)
X-andY-InterceptMethod
PracticeProblems
ToSolve:
-To;indthex-interceptofalinesetyintheequationequalto0andsolve forx.
-To;indthey-interceptofalinesetxintheequationequalto0andsolve fory.
Section 6X- and Y-Intercept Method
53
Example: Find the x and y intercepts of: 4x + y = 8
PracticeProblems
ToSolve:
-Graphthe;irstlineusingslope-interceptformorx-andy-intercepts method.
-Onthesamegrid,graphthesecondline.
-Ifthelinesintersect,determinethecoordinatesofthepointandcheck thatthepointisasolutiontobothequations.
-Ifthelinesareparallel(havethesameslope),thenthereisnosolution.
-Ifthelinesarethesamelinethentherearein;initelymanysolutions.
Section 7Graphing Systems of Equations
54
Graph the system of equations: y = 2x +1 and y = x + 6
Example:
Graph the system of equations: y = 2x - 1 and 2y = 4x - 2 2y = 4x - 2 2 2
y = 2x - 1
Example:
Graph the system of equations: y = 4x - 4 and y = 4x + 3
Example:
PracticeProblems
ToSolve:
-Useeitherslope-interceptformorx-andy-interceptsmethodto;indtwo points.
-Connectthepointswithasolidlineiftheinequalityis≤or≥.
-Connectthepointswithadottedlineiftheinequalityis<or>.
-Shadethegraphonthesideofthelinethatmakesallthepointstheretrue fortheinequality.
-Chooseapointononesideoftheline:abovethelineif>or≥,below if<or≤,andcheckintheinequalitytotestifitisatruestatement.
Section 8Graphing Inequalities
55
Example: Graph y > x - 3 m = 1, b = (0, 3) dotted line Check (0,0)
y > x - 3 0 > 0 - 3 0 > -3
Example: Graph: y < 1x + 2 3 Slope: 1 y-int: (0, 2) 3 Solid line Check: (0, 0) y < 1x + 2 3 0 < 1(0) + 2 3 0 < 0 + 2 0 < 2
PracticeProblems
Tosolve:
-Graphbothinequalitiesandshadeeach(usedifferentshadingforeach).
-Chooseapointwherebothshadingsoverlapandcheckthepointineach inequalitytoseeifitcreatestruestatements.Iftrue,labelthearea“S”for solutionset.
Section 9Graphing Systems of Inequalities
56
Graph the following system of inequalities: y > 2x + 1 and 2y < −x + 6
Example:
POLYNOMIALSChapter 7
7.1 Addition and Subtraction7.2 Properties of Exponents7.3 Scientific Notation7.4 Multiplication7.5 Division
OrderingPolynomials
Polynomialsshouldbeplacedindescendingdegreeorder.To;indthedegreeofapolynomialaddtogetheralloftheexponentsineachterm.Iftwotermshavethesamedegree,placetheminorderalphabetically.
PracticeProblems1AddingPolynomials
Whenaddingpolynomials,addtogetherthosepolynomialsthatareliketerms.Remember,liketermshavethesamevariablesandthesameexponents.Toaddthem,addthecoef;icientsandkeepthebaseandexponentsthesame.Placeinthecorrectpolynomialorder.
SubtractingPolynomials
Whensubtractingpolynomials,subtractthosepolynomialsthatareliketerms.Ifthereisasubtractionsignoutsideoftheparenthesesmakesuretodistributethesubtractionsigntoeachtermbeforecombiningtheliketerms.Placeinthecorrectpolynomialorder.
PracticeProblems2
PracticeProblems3
Section 1Addition and Subtraction
58
Example: Place the polynomial in the correct order: 5y² + 7xy − 2x² + 3y − 8 Degree of two: (Place alphabetically) − 2x² + 7xy + 5y² Degree of one: 3y Constants: − 8 Correct Order: − 2x² + 7xy + 5y² + 3y − 8
Example: Add: (4x² + 6x − 7) + (−5x² −6x)
4x² + 6x − 7 + −5x² −6x −1x² + 0x − 7 Answer: −x² − 7
Example: Subtract: (6x² + 2x − 8) − (−4x² + 3x −4)
6x² + 2x − 8 + 4x² − 3x + 4 10x² − 1x − 4 Answer: 10x² − x − 4
MultiplicationProperties
•MultiplyingExponents-whenmultiplyingexponentswiththesamebase,addthe exponentsandkeepthebasethesame.
• Example:
€
x 2 ⋅ x 4 = x 6
•ZeroExponents-anynumberortermraisedtoanexponentofzeroisalways equalto1.
• Example:
•PowerofaPowerMultiplication-whenoneexponentisraisedtoanother exponent,multiplytheexponentsandkeepthebasethesame.
• Example:
DivisionProperties
•DividingExponents-whendividingexponentswiththesamebase,subtractthe exponentsandkeepthebasethesame.
• Example:
•PowerofaPowerDivision-whenafractionwithexponentsisraisedtoanother exponent,multiplytheoutsideexponenttobothoftheexponentsinthe numeratoranddenominatorandkeepthebasesthesame.
•
PracticeProblems1
NegativeExponents
• Sincetherearenonegativeexponents,allnegativeexponentsmustbeturnedintopositiveexponents.Todothis,movethenegativeexponenttothedenominatorofafractionandmaketheexponentpositive.Ifthereisanegativeexponentinthedenominatorofafraction,moveittothenumeratorandmakeitpositive.
•
Example:
PracticeProblems2
PracticeProblems3
!! = 1!
Section 2Properties of Exponents
59
(!!)! = !!!
€
x 6 ÷ x 4 = x 2
€
a2
b−2= a2b2
Example:
€
x 3
y 4
"
# $
%
& '
2
=x 6
y 8
Example:
€
4 −2 =116
€
142
=116
StandardNotationtoScientiGicNotation
• Scienti;icnotationisusedtoexpressverylargeorverysmallnumbers.Whenwritinganumberinscienti;icnotation,movethedecimalpointtomakeanumberthatisgreaterthanorequalto1butlessthan10.Multiplythenumberbyapoweroften.Todeterminethepoweroftencounthowmanyplacesthedecimalpointwasmoved.Ifthedecimalwasmovedtotheleft,theexponentwillbepositive.Ifitwasmovedtotheright,theexponentwillbenegative.
• Example:4,621,000canbewritteninscienti;icnotationas:
• Example:0.00462canbewritteninscienti;icnotationas:
ScientiGicNotationtoStandardNotation
• Whenwritinganumberinstandardnotation,movethedecimalpointaccordingtotheexponentinthepowerof10.Iftheexponentispositive,movethedecimalpointtotheright.Iftheexponentisnegative,movethedecimalpointtotheleft.
• Example:canbewritteninstandardnotationas:4,621,000
• Example:canbewritteninstandardnotationas:0.00462
PracticeProblems1
MultiplyingwithScientiGicNotation
• Whenmultiplyingwithscienti;icnotation,multiplythefactors,andthenmultiplythepowersoften.Tomultiplythepowersoften,addtheexponents.Ifthefactorsmultiplytoanumbergreaterthanorequaltoten,adjustthefactorandexponentaccordinglytoproperscienti;icnotation.
DividingwithScientiGicNotation
• Whendividingwithscienti;icnotation,dividethefactors,andthendividethepowersoften.Todividethepowersoften,subtracttheexponents.Ifthefactorsdividetoanumberlessthanorequaltoten,adjustthefactorandexponentaccordinglytoproperscienti;icnotation.
PracticeProblems2
4.621!×!10!!
Section 3Scientific Notation
60
4.62!×!10!!!
4.621!×!10!!
4.62!×!10!!!
Multiplying with Scientific Notation
Dividing with Scientific Notation
MultiplyingMonomials
• Whenmultiplyingmonomials,multiplythecoef;icients,keepthevariablethesame,andaddtheexponents.Ifatermisoutsideofparenthesesdistributeittoeachtermintheparentheses.
PracticeProblems1MultiplyingBinomials
• Whenmultiplyingbinomials,multiplyeachterminthe;irstparenthesesbyeachterminthesecondparentheses.UsethetermsFOILtohelprememberthesteps.MultiplytheFIRSTterms,thentheOUTERterms,nexttheINNERterm,nexttheLASTterms.Combineanyliketermsattheend.
PracticeProblems2
MultiplyingPolynomials
• Whenmultiplyingpolynomials,multiplyeachterminthe;irstparenthesesbyeachterminthesecondparentheses.Combineanyliketermsattheend.
PracticeProblems3
AreaWordProblems
PracticeProblems4
Section 4Multiplication
61
Multiplying Polynomials
Tosolveanareawordproblem:
-Setuptheoriginalshape’sletstatement(s)andpicture.
-Setupthenewshape’sletstatement(s)andpicture.
-Identifytheformula(s)neededtosolvetheproblem.
-Writeanequationthatrepresentsthegiveninformation.
AreaofaSquare:
!! = ! !!!
AreaofaRectangle:
!! = !!"! Area Word Problems without
Factoring
Example: Multiply: (x + 6)(x − 2) F: x(x) = x² O: x(-2) = -2x I: 6(x) = 6x L: 6(-2) = -12 Answer: x² + 4x - 12
Example:
Example: Multiply: (−4x²)(6x³y) −4(6) = −24 x²(x³) 3+2=5 x⁵ y Answer: −24x⁵y
DividingaMonomialbyaMonomial
• Whendividingmonomials,dividethecoef;icients,keepthevariablethesame,andsubtracttheexponents.
PracticeProblems1DividingaPolynomialbyaMonomial
• Whendividingapolynomialbyamonomial,eachterminthenumeratorshouldbedividedbythemonomialinthedenominator.Dividethecoef;icients,keepthevariablethesame,andsubtracttheexponents.
PracticeProblems2
DividingPolynomialsUsingLongDivision
• Whendividingapolynomialbyabinomialortrinomial,uselongdivisioninordertosolve.Thestepsforlongdivisionofpolynomialsarethesameasregularlongdivision.Thereareafewthingstokeepinmindwhensettingupthedividend(thetermbeingdivided).Thedividendshouldhavedescendingexponents.Ifadegreeismissing,additinwithazeroasthecoef;icient.Iftherearetwovariablesinthedividendmakesureitisincorrectpolynomialorder.
PracticeProblems3
Section 5Division
62
Dividing Polynomials 1
Dividing Polynomials 2
Dividing Polynomials with
2 Variables
Dividing Polynomials with
Remainders
Example: Divide: −16x²y²z 8xyz −16 = -2 x² = x y² = y z = 1 8 x y z Answer: -2xy
Example: Divide: 12x³y² − 8xyz − 4x 12x³y² = −3x²y² − 8xyz = 2yz − 4x − 4x Answer: −3x²y² + 2yz
FACTORING POLYNOMIALS
Chapter 8
8.1 Greatest Common Factor8.2 Difference of Two Squares and Grouping8.3 Trinomials8.4 Trinomials with Leading Coefficients8.5 Factoring Completely8.6 Quadratic Equations8.7 Quadratic Equation Word Problems8.8 Graphing Parabolas
GreatestCommonFactor
• Whenitcomestofactoringpolynomials,thereareseveralmethodstouse.The;irstmethodthatyoushouldALWAYSlookforisaGreatestCommonFactor.
PracticeProblems
ToFindtheGCF:
-Lookateachterminthepolynomial.
-FindtheGREATESTfactorofthecoef;icientsthattheyALLhavein common.
-FindtheHIGHESTexponentofeachvariablethattheyALLhavein common.
-Thesecommonfactorsshouldallgooutsideoftheparentheses.
-Anyremainingpartsofthetermsremaininsideoftheparentheses.
Section 1Greatest Common Factor
64
Example: Factor: 12x⁴ − 3x³ + 9x² Greatest common factor is 3x² Factoring: 3x²(4x² − x + 3)
Example: Factor: a²b³ + ab² Greatest common factor is ab² Factoring: ab²(ab + 1)
Example: Factor: 4x + 16 Greatest common factor is 4 Factoring: 4(x + 4)
DifferenceofTwoSquares
• Whenanexpressionisintheforma²–b²,thewayyoufactoriscalled“DifferenceofTwoSquares”(DOTS).ThekeyhereistheDIFFERENCE.ThereMUSTbeasubtractionsignbetweentheperfectsquares.
PracticeProblems1
Grouping
• IfyouareunabletofactorusingtheGreatestCommonFactorforalloftheterms,youmaybeabletogroupwithinthepolynomialinordertouseaGCF.Youneed4termstousegrouping.
PracticeProblems2
**Remember,eachpartoftheexpressionmustbeaperfectsquare--variablesareaperfectsquareiftheyhaveanevenexponent**
Section 2Difference of Two Squares and Grouping
65
To;indtheDifferenceofTwoSquares:
-Setuptwopairsofparentheses.
-EachsquarerootgoesintoBOTHparentheses.
-Putoppositesignsineachpair.
Totakethesquarerootofvariables,dividetheexponent
Totakethesquarerootofafraction,takethesquarerootofthe
numeratorandthedenominator.
DOTS 1 DOTS with Fractions
ToFactorUsingGrouping:
-GroupthetermsintopairssoeachpairhasaGCF.
-Factoreachsetofterms.
-TheGCFsoutsidebecomeonesetofparenthesesandtheremaining partsofthetermsbecometheotherparentheses.
-Thetermsinsideoftheparenthesesoriginallymustbethe same.Factorouta-1ifyouneedtochangethesignsinoneset ofparentheses.
Grouping
Example: Factor: a² − 81 √a² = α √81 = 9 Factoring: (a + 9)(a − 9)
Example: Factor: x² + xy + 4x + 4y
x² + xy 4x + 4y x(x + y) 4(x + y) Answer: (x + y)(x + 4) Check: (x + y)(x + 4) = x² + xy + 4x + 4y x² + 4x + xy + 4y = x² + xy + 4x + 4y ✔️
TrinomialswithoutLeadingCoefGicients
• Trinomialsarewrittenintheform“ax²+bx+c”where“a,”“b,”and“c”arenumbers.Inthiscase,“a”isalways1.
PracticeProblems1
PracticeProblems2
ToFactor:
-Setuptwopairsofparentheses(x+/-_____)(x+/-_____).
-Lookatthesigninfrontof“c”.
-Ifitispositive,thesignsinparenthesesaresameas“b”.
-Ifitisnegative,thesignsareopposite,with“b”tellingusthe signofthelargerfactor.
-Findfactorsof“c”thatadduptothe“b”value.
-UseFOILtocheck.
Section 3Trinomials
66
Trinomials 1 Trinomials 2 Trinomials 3
FactoringTrinomialswithaLeadingCoefGicient
PracticeProblems
ToFactor:
TheEyeglassMethod
-Takeoutanygreatestcommonfactors.
-Multiply“a”and“c”together.
-Findfactorsofthatnumberthataddupto“b”.
-Useyoursignstohelpyou:apositive“ac”meansusethesame signsinyourfactors,whileanegative“ac”meansusedifferent signsinyourfactors.
-Replaceyour“bx”withthevaluesthatadduptoit.
-Usethegroupingmethodto;inishfactoring.
-CheckbyFOILtomakesureyouransweriscorrect.
Section 4Trinomials with Leading Coefficients
67
Trinomials with Leading
Coefficient 1
Trinomials with Leading
Coefficient 2
Trinomials with a Leading
Coefficient 3
FactoringCompletely
PracticeProblems
ToFactorCompletely:
-StartbylookingforaGCF.
-TaketheGCFoutifpossible.
-Factorwhatremains.
-Checkyournewpolynomialstoseeiftheycanbefactoredanyfurther.
Section 5Factoring Completely
68
Youmayhavetofactorseveraltimesbeforeapolynomialisfactoredcompletely.
**UseGCF,DOTS,Grouping,TrinomialFactoring,andEyeglassFactoring**
Factoring Completely 1
Factoring Completely 2
Example: Factor: 4x² - 16
4(x² - 4) 4(x - 2)(x + 2)
Check: 4(x - 2)(x + 2) = 4x² - 16 (4x - 8)(x + 2) = 4x² - 16 4x² + 8x - 8x - 16 = 4x² - 16
4x² - 16 = 4x² - 16 ✔️
Example: Factor: 2x² - 4x - 30
2(x² - 2x -15) 2(x - 5)(x + 3)
Check: 2(x - 5)(x + 3) = 2x² - 4x - 30
(2x - 10)(x + 3) = 2x² - 4x - 30 2x² + 6x - 10x - 30 = 2x² - 4x - 30
2x² - 4x - 30 = 2x² - 4x - 30 ✔️
SolvingQuadraticEquations
PracticeProblems
Tosolve:
-Combineanyliketerms.
-Getalltermsontoonesideoftheequationsothatitisequaltozero.
-Factorcompletelythesidewiththeterms.
-Seteachfactorequaltozeroandsolve.
-CheckbypluggingEACHanswerintotheoriginalequation.
Section 6Quadratic Equations
69
Theanswerstotheseproblemsarecalled“roots.”Theseareallofthevaluesofxwhenthe
equationisequalto0.
Quadratic Equation 1
Quadratic Equation 2
Example: Solve: x² - 3x - 18 = 0 (x + 3)(x - 6) = 0 x + 3 = 0 x - 6 = 0 - 3 - 3 +6 +6 x = - 3 x = 6 {-3, 6} Checks: x² - 3x - 18 = 0 x² - 3x - 18 = 0 (-3)² -3(-3) -18 = 0 (6)² -3(6) - 18 = 0 9 + 9 - 18 = 0 36 - 18 - 18 = 0 0 = 0 ✔️ 0 = 0 ✔️
QuadraticEquationWordProblems
PracticeProblems
ToSolve:
-SetupLetStatement(s)inONEvariable.
-Setupanequation.
-Movealltermstoonesidetogetequaltozero.
-Factor.
-Solve.
-Determineifanyanswerdoesnotmakesense.
Section 7Quadratic Equation Word Problems
70
Quadratic Equation Word
Problem 1
Quadratic Equation Word
Problem 2
GraphingParabolas
• Thegraphofaquadraticequationisaparabola.Thesearecurvesthatopenup(likeasmile)ordown(likeafrown).Thewaytodeterminethedirectionislookingatthe“a”coef;icient.Ifitispositive,yourparabolawillopenup,andifitisnegative,yourparabolawillopendown.
• Parabolasaresymmetricalsotheyhavewhatiscalledan“axisofsymmetry”thatrunsverticallydownthemiddle.Thisimaginarylineiswherethegraphchangesdirectionandisthereforecalledtheturningpoint.
PracticeProblems1
PracticeProblems2
FormulaforAxisofSymmetry:x=-b/2a
Section 8Graphing Parabolas
71
ToGraph:
-Getequationinstandardform(equaltozero).
-Identifyyour“a,”“b,”and“c”values.
-FindtheAxisofSymmetry.
-Setupatableofvaluestograph.
-3Columns:x-value,equation,y-value
-Yourtableshouldhave5valueswiththemiddleonebeingyour turningpoint.
-Plotthe5pointsandyourROOTSonyourgraph.Remember,your rootsarewheretheparabolacrossesthex-axisandtheanswertoa quadraticequation.
-Connectyourpoints—it’sacurve,nota“V”.
Rememberthataverticallineisx=#
Example: Graph: -x² - 3x +6 = y a = -1, b = -3, c = 6 axis of symmetry: x = -b = -(-1) = -1
2a 2(-1) 2 table of values: roots: -x² -3x +6 = 0 -1(x² +3x -6) = 0 -1(x - 2)(x + 3) = 0 -1 = 0 x - 2 = 0 x + 3 = 0 ❌ +2 +2 -3 -3 x = 2 x = -3 (2, 0) (-3, 0)
Example:
RATIONAL EXPRESSIONS
Chapter 9
9.1 Simplifying9.2 Multiply and Dividing9.3 Adding and Subtracting with a Common Denominator9.4 Adding and Subtracting with a Non-Common Denominator
SimplifyingRationalExpressions
• Arationalexpressionisafractionthatcontainsvariables.Itcanalsobecalledanalgebraicfraction.
PracticeProblems
Tosimplify:
Findthegreatestcommonfactorofboththenumeratoranddenominatorandcancelthem.
Section 1Simplifying
73
Forbinomialandtrinomialexpressionsinafraction:
a)Factorboththenumeratoranddenominatorcompletely.
b)Cancelanycommonfactors.
Example:Simplify
sincexisthecommonfactor,cancelthemandansweris
3!4!!!!!!
34!
Example:Simplify
cancelallofthecommonfactorsandtheansweris3x
6!!2! !!!!!
!
Example:!!4x!+!2!!!!factors!to!!!!!!!!2(2x!+!1)!!!!!!!!!!!!!cancel!out!the!!(2x!+!1)!!!and!the!answer!is!!!!!!!2!!!!!!!!!!!!!!!!!!!!!!!!!!!!4x2!–!1!!!!!!!!!!!!!!!!!!!!!!!!(2x!+!1)(2x!–!1)!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!2x!–!1!!!!Example:!!x2!+!4x!+!3!!!=!!(x!+!3)(x!+!1)!!cancel!out!the!!(x!+!3)!!!and!the!answer!is!!!x!+!1!!!!!!!!!!!!!!!!!!!!!x2!+!5x!+!6!!!!!!!!(x!+3)(x!+!2)!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!x!+!2!!
Example:
Example:
MultiplyingandDividingRationalExpressions
• Tomultiply:factorcompletelyallnumeratorsanddenominatorsandcancelallcommonfactorsfromanynumeratortoanydenominator.Thenmultiplyacrossusinganyremainingfactors.
• Todivide:First,rewritetheproblemchangingthefractionafterthedivisionsigntoitsreciprocalandthenfollowmultiplicationrules.
PracticeProblems
!
Example:!!!!x!–!3!!!•!!x2!+!7x!+!12!!•!!x2!–!1!!!!!!!factor:!!!!!!!!!x!–!3!!!!!!!•!!(x!+!3)(x!+!4)!!•!!(x!+!1)(x!–!1)!! !!!!!!!!x2!–!9!!!!!!!!!4x!+!16!!!!!!!!!!!!x!+!1! !!!!!!!!!!!!!!!!!(x!+!3)(x!–!3)!!!!!!!4(x!+!4)!!!!!!!!!!!!!!!!!!x!+!1!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!Cancel!any!common!binomials!and!answer!!!!!!!x!–!1!!!! ! ! ! ! ! ! ! ! ! !!!!!!!!!4!!
Section 2Multiplying and Dividing
74
!
Example:!!!!x2!–!1!!÷!!2x!+2!!!!rewrite!as!!!!!x2!–!1!!!•!!x2!–!9!!!!!factor!!(x!+!1)(x!–!1)!!•!!(x!+!3)(x!–!3)!!!!!!!!!!!!!!!!!!!!!!!!x!+!3!!!!!!!x2!!–!9!!!!!!!!!!!!!!!!!!!!!!!!!!!!x!+!3!!!!!!!!2x!+!2!!!!!!!!!!!!!!!!!!!!!(x!+!3)!!!!!!!!!!!!!!!!!2(x!+!1)!!!!!!! ! ! cancel!common!factors!and!the!answer!is:!!(x!–!1)(x!–!3)!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ! ! ! ! !!!!!!!!!!!!!!!!!!!!!!!!!2!!
Example:
Example:
AddingandSubtractingRationalswithCommonDenominators
• Toaddorsubtractwhenthedenominatorsarethesameaddorsubtractthenumeratorscombiningliketerms.Thensimplifytheanswer.
PracticeProblems
Rememberwhensubtractingmorethanoneterm,distributethenegativesignoveralltermsinthesecond
denominator.
Section 3Adding and Subtracting with a Common Denominator
75
!Example:!!!!2x!+!3!!+!!2x!+!1!!=!!4x!+!4!!=!!4(x!+!1)!!=!!4!!!!!!!!!!!!!!!!!!!!!!!!!!!x!+!1!!!!!!!x!+!1!!!!!!!!!!x!+!1!!!!!!!!!x!+!1!!!Example:!!!!3x!+!2!!–!!x!–!4!!!=!!2x!+!6!!=!!2(x!+!3)!!!=!!x!+!3!!!!!!!!!!!!!!!!!!!!!!!!!!2x!!!!!!!!!!!!2x!!!!!!!!!!!!!!2x!!!!!!!!!!!!!!2x!!!!!!!!!!!!!!!!!x!!
Example:
Example:
AddingandSubtractingRationalswithDifferentDenominators
PracticeProblems
Toaddorsubtractwhenthedenominatorsaredifferent,
-Factoranydenominatorsthatcanbefactoredto;indwhattheyhavein common.
-Converttolikedenominators.
-Addorsubtractthenumeratorscombiningliketermsandanswerin simpli;iedform.
Section 4Adding and Subtracting with a Non-Common Denominator
76
!Example:!!!!!x!+!1!!+!!!x!+!1!!!!=!!!2x!+!2!!+!!3x!+!3!!!=!!5x!+!5!!!!or!!5(x!!+!1)!!!!!!!!!!!!!!!!!!!!!!!!!!!3x!!!!!!!!!!!2x!!!!!!!!!!!!!!!6x!!!!!!!!!!!!!6x!!!!!!!!!!!!!!6x!!!!!!!!!!!!!!!!!6x!!
Example:
Adding with Different
Denominators
ROOTS OF NUMBERS
Chapter 10
10.1 Finding the Root10.2 Simplifying10.3 Adding and Subtracting10.4 Multiplying and Dividing10.5 Solving Equations10.6 Rationalizing the Denominator10.7 Pythagorean Theorem
TerminologyofRadicals:
• Example:,2isthecoef;icient,3istheindex,125istheradicand.
SquareRoot
• Totakethesquarerootofanumber,determinewhatnumbermultipliedbyitselfgivesyouthenumberundertheradical(theradicand).Anyradicalwithoutanindex,hasanindexoftwo,meaningtakethesquareroot.
PerfectSquares
• Numbersthatyoucantakethesquarerootofarecalledperfectsquares.Theanswerforaperfectsquareisaninteger.To;indtheperfectsquareofanumber,determinewhatintegerwhenmultipliedbyitselfgivesyoutheradicand.
• Example:,4multipliedbyitselfequals16.
CubeRoot
• Takingthecuberootofanumberisrepresentedbyanindexofthreeoutsidetheradical.Totakethecuberootofanumberdeterminewhatnumbermultipliedbyitselfthreetimesgivesyoutheradicand.
• Example:,2multipliedbyitselfthreetimesequals8.
RaisingaRadicaltoanExponent
• Whenaradicalisraisedtoanexponenttheradicalandexponentcanbedroppediftheindexandtheexponentarethesame.
• Example:
Rationalvs.Irrational
• Radicandsthatyoucantakethesquarerootofarerationalnumbers.Numbersthatyoucannottakethesquarerootofareirrationalnumbers.
• Example:isrational.
• Example:isirrational.
TakingtheRootofVariables
• Totaketherootofavariable,dividetheexponentbytheindexandkeepthevariablethesame.
• Example:,multipliedbyitselfequals.
2 1253
Section 1Finding the Root
78
€
16 = 4
83 = 2
7( )2= 7
25 = 5
€
7 = 2.64575131106...
x16 = x8 x8 x16
RadicalswithFractions
• Totaketherootofafraction,taketherootofthenumeratorandtherootofthedenominator.
• Example:
• Example:
PracticeProblems
8125
3!
"#
$
%&=25
79
916 =
34!
SimplifyingRadicals
Whenaradicalisnotaperfectsquare,theradicalcansometimesbesimpli;ied.Tosimplifyaradical,simplifytheradicandintofactors.Anyfactorsthatareperfectsquaresshouldbesimpli;ied.Ifafactorisnotaperfectsquare,checktoseeifitcanbefactoredfurther.Factorsareinsimplestformwhenthesquarerootsofperfectsquaresaretaken,andallremainingradicandsareprimenumbers.Toputtheanswertogether,multiplyallperfectsquaresforthecoef;icient,multiplyanyradicandstogethertobecomethe;inalradicand.
SimplifyingVariablesinaRadical
Totakethesquarerootofavariablewithanevenexponent,dividetheexponentbytwo.Totakethesquarerootofavariablewithanoddexponent,subtractonefromtheexponent(whichshouldstayundertheradicalsign),andthendividewhatisremainingbytwotogetitssquareroot.Theevenexponentthatyoucantakethesquarerootofbecomespartofthecoef;icient.Theoddexponentofonebecomespartoftheradical.
PracticeProblems
Section 2Simplifying
80
Simplifying Radicals
Simplifying Radicals 2
Example: Simplify: √a⁵b⁶c⁷ √a⁵ √b⁶ √c⁷ √a⁴ √a b³ √c⁶ √c a² c³ a²b³c³√ac
Example:
Simplify: √18 √9 √2
3 3√2
OR Simplify: √18 √6 √3 √2 √3
√2 √3 √3
3√2
AddingandSubtractingRadicals
Radicalscanonlybecombinediftheyareliketerms.Radicalsareliketermswhentheyhavethesameradicand.Inordertocombinelikeradicals,addorsubtractthecoef;icientsandkeeptheradicandthesame.Allradicalsshouldbeinsimplesttermsbeforeaddingorsubtractingthem.
PracticeProblems
Section 3Adding and Subtracting
81
Adding Radicals Subtracting Radicals
Example: Add: √6 + 4√6 + 5√6
1 + 4 + 6 = 10 Answer: 10√6
Example: Subtract: √5 - 6√5 - 7√5
1 - 6 - 7 = -12 Answer: -12√5
MultiplyingandDividingRadicals
Allradicalscanbemultipliedanddivided.Multiply/Dividethecoef;icientsandmultiply/dividetheradicands.Simplifytheradicalsattheend.
PracticeProblems
Section 4Multiplying and Dividing
82
Multiplying Radicals
Multiplying Radicals 2
Dividing Radicals
Example:
Example: Multiply: (4√2)(2√3)
Answer: 8√6
SolvingEquationswithRadicals
Tosolveanequationwitharadical,theradicalneedstobeisolatedononesideoftheequation.Thatmeansanytermsthatareoutsideoftheradicalneedtobemovedtotheothersideusinginverseoperations.Oncetheradicalisisolated,squareeachsideoftheequation(thiswilleliminatethesquareroot).Solvetheequationandcheck.
PracticeProblems
Section 5Solving Equations
83
Solving Equations with
Radicals
Example: Solve: √x + 1 = 6
(√x + 1)² = (6)² x + 1 = 36 x = 35
Check: √x + 1 = 6 √35 + 1 = 6
√36 = 6 6 = 6 ✔️
RationalizingtheDenominator
Rationalizingthedenominatorofafractionmeansremovingtheradicalfromthedenominator.Todothis;indaradicalthatthedenominatorcanbemultipliedbywhichwillresultinaperfectsquare.Whenthedenominatorismultipliedbyaradical,thenumeratormustbemultipliedbythesameradical.Simplifytheradicalinthenumeratorandsimplifythefractionalcoef;icientattheend.
PracticeProblems
Section 6Rationalizing the Denominator
84
Rationalizing the Denominator
Example: Simplify: 2 √5 2 √5 = 2√5 = 2√5 √5 √5 √25 5
PythagoreanTheorem
PythagoreanTheoremexplainstherelationshipbetweenthethreesidesofarighttriangle.Thetheoremstatesthatthesumofthesquaresofthelegsofarighttrianglearealwaysequaltothesquareofthehypotenuseoftherighttriangle.
PracticeProblems
Formula:
(aandbrepresentthelegs,whilecrepresentsthehypotenuse,whichisalwaysoppositetherightangle).
Section 7Pythagorean Theorem
85
!! + !! = !!!
Pythagorean Theorem
3 in.
4 in. x
a² + b² = c² 3² + 4² = c² 9 + 16 = c² 25 = c² √25 = √c² 5 in. = c
Example: Find the missing side.