-
8/14/2019 2E Worksheet 2 (Simultaneous Eqns - Eliminatn
Method)
1/4
CORALSECONDARY CHOOLELEMENTARYMATHEMATICSWORKSHEET :
SIMULTANEOUS QUATIONS(ELTMTNATTONETHOD)Name: ( )Sec2l Date:1.
Elimination MethodMethod:L Determinewhich variableyou want to
eliminate. Is it the "x" or is it the "y" that youwant to eliminate
getrid offl).2. Ensure hat the coefficient of the variable that you
have decided o eliminate s thesame. To do this you may be required
o multiply a certain factor into one of theequations o that the
coefficientsbecome he same. There are somecaseswhereyoumay be
required o multiply different actors o eachequationso that the
coefficientofthe variableyou havedecided o eliminateare he same.3.
Look at the coefficientof the variables hatyou want to eliminate.
If the signsare hesame e.g. f both coefficients re 2" or both
coefficients re -2 ") thenwe subtractoneequation rom another. f the
signsaredifferent (e.g. 2" and" -2") thenwe addbothequations.
, 4. We will then solve for the unknown anduse this value to
find the other unknownbysubstituting he value nto any of the two or
iginal equations.5. To check f your solution s correct,substitute
he values of x andy into any of theoriginal equationandyou
shouldobtain he right hand side.2. Examples2.1 Solve he pairof
simultaneousquations:
x*Y=)x*Y=4
Eliminate "x" Eliminate'6y"
LEARN.INNOVATE ND BUILDTHEFUTURE!lec(2007) Page
-
8/14/2019 2E Worksheet 2 (Simultaneous Eqns - Eliminatn
Method)
2/4
2E Worksheet : Simultaneous quations EliminationMethod)
2.2 Solve hepair of simultaneous quations:4x+5Y =122x +3r
=12
2.3 Solve hepairof simultaneousquations:7x-2Y=$5x 3Y : -2
LEARN,INNOVATE ND BUILDTHEFUTURE! Page
-
8/14/2019 2E Worksheet 2 (Simultaneous Eqns - Eliminatn
Method)
3/4
2E Worksheet : Simultaneous ouations El.iminationMethod)
2.4 Solvehepairof simultaneousquations:3x-2Y=J2x+7Y=)J
2.5 Solve hepair of simultaneous quations:I5x+:v=13a/J7x-y=5
LEARN, NNOVATEAND BUILD THE FUTURE! Page3
-
8/14/2019 2E Worksheet 2 (Simultaneous Eqns - Eliminatn
Method)
4/4
2E Worksheet : Simultaneous quations EliminationMethod)
2.6 Solve hepairof simultaneousquations:x.y .JZY I, '" t "t
-1
22
2.7 There are two queuesat a bus stop at a certain ime. The
numberof people n thequeues rex andy respectively ndx> y.(i) If
the difference n the numberof people n these wo queues s 10, form
anequationconnecting andy.(ii) If the first queue is twice as long
as the secondqueue, form an equationconnecting andy.(iii) Solve the
simultaneousequationsobtained n (i) and (ii). Hence find
thenumberof people n eachqueue.
SAil : Ex 5.4 Qlg,2a, gHAil: Ex 5.4 Q1b,e,2b, e,h, 3;
OptionalQuestion:Q5LEARN.INNOVATE ND BUILDTH EFUTUREI Page4
