Chapter 5 Review Chapter 5 Review

5.1 Write Linear Eqns in Slope-Intercept Form

5.1 Write Linear Eqns in Slope-Intercept Form

Example 1

Write an equation of the line shown.

Step 1: y = mx + b

Step 2: Find b.

(y-intercept)

b = 4

Step 3: Find m.

(slope = rise/run)

m = -2/3

Step 4: Write equation

y = (-2/3)x + 4

Step 1: y = mx + b

Step 2: Find b.

(y-intercept)

b = 4

Step 3: Find m.

(slope = rise/run)

m = -2/3

Step 4: Write equation

y = (-2/3)x + 4

Assignment: Pg. 345Assignment: Pg. 345

# 4 - 6# 4 - 6

You have a $25 gift card for a bagel shop. A bagel costs $1.25. Write an equation that gives the amount (in dollars) that remains on the card as a function of the total number of bagels you have purchased so far. How much money is on the card after you buy 2 bagels?

T = 25 - 1.25b (b= number of bagels, T = total)

T = 25 - 1.25(2) = $22.50

You have a $25 gift card for a bagel shop. A bagel costs $1.25. Write an equation that gives the amount (in dollars) that remains on the card as a function of the total number of bagels you have purchased so far. How much money is on the card after you buy 2 bagels?

T = 25 - 1.25b (b= number of bagels, T = total)

T = 25 - 1.25(2) = $22.50

5.2Use Linear Equations in Slope-Intercept Form

5.2Use Linear Equations in Slope-Intercept Form

Example 2Write an equation of the line that passes through the point (-2,-6) and

has a slope of 2.Step 1: y = mx + bStep 2: Find b (y-intercept) y = mx + b -6 = 2(-2) + b -6 = -4 + b +4 +4 -2 = bStep 3: Write Equation y = 2x - 2

Example 2Write an equation of the line that passes through the point (-2,-6) and

has a slope of 2.Step 1: y = mx + bStep 2: Find b (y-intercept) y = mx + b -6 = 2(-2) + b -6 = -4 + b +4 +4 -2 = bStep 3: Write Equation y = 2x - 2

Assignment: Pg. 346Assignment: Pg. 346

# 8 - 10# 8 - 10

5.4Write Linear Equations in Standard Form

5.4Write Linear Equations in Standard Form

Example 3

Write an equation in standard form of the line shown.

(-1,1) and m = -2

Example 3

Write an equation in standard form of the line shown.

(-1,1) and m = -2

(-1,1) and m = -2(-1,1) and m = -2

Step 1: y = mx + b

Step 2: Find b

1 = (-2)(-1) + b

1 = 2 + b

-2 -2

-1 = b

Step 3: Write equation

y = -2x - 1

Step 1: y = mx + b

Step 2: Find b

1 = (-2)(-1) + b

1 = 2 + b

-2 -2

-1 = b

Step 3: Write equation

y = -2x - 1

Assignment: Pg. 347Assignment: Pg. 347

# 15 - 16# 15 - 16

5.5Write Equations of Parallel and Perpendicular Lines

5.5Write Equations of Parallel and Perpendicular Lines

Example 4

Write an equation of the line that passes through

(-4,-2) and is perpendicular to the line y = 4x - 7.

Hint: Perpendicular lines have slopes that are the negative reciprocal of each other.

Step 1: Find slope.

y = 4x -7

m = 4, so slope of perpendicular line is - 1/4.

Example 4

Write an equation of the line that passes through

(-4,-2) and is perpendicular to the line y = 4x - 7.

Hint: Perpendicular lines have slopes that are the negative reciprocal of each other.

Step 1: Find slope.

y = 4x -7

m = 4, so slope of perpendicular line is - 1/4.

Write an equation of the line that passes through (-4,-2) and is perpendicular to the line

y = 4x - 7.

Write an equation of the line that passes through (-4,-2) and is perpendicular to the line

y = 4x - 7.

Step 2: Find b.

y = mx + b

-2 = (-1/4)(-4) + b

-2 = 1 + b

-1 -1

-3 = b

Step 3: Write Equation

y = (-1/4)x - 3

Step 2: Find b.

y = mx + b

-2 = (-1/4)(-4) + b

-2 = 1 + b

-1 -1

-3 = b

Step 3: Write Equation

y = (-1/4)x - 3

5.5Write Equations of Parallel and Perpendicular Lines

5.5Write Equations of Parallel and Perpendicular Lines

Example 5

Write an equation of the line that passes through

(-4,-2) and is parallel to the line

y = 4x - 7.

Hint: Parallel lines have the same slopes.

Step 1: Find slope.

y = 4x - 7

m = 4, so the slope of a parallel line is 4.

Example 5

Write an equation of the line that passes through

(-4,-2) and is parallel to the line

y = 4x - 7.

Hint: Parallel lines have the same slopes.

Step 1: Find slope.

y = 4x - 7

m = 4, so the slope of a parallel line is 4.

Write an equation of the line that passes through (-4,-2) and is parallel to the line

y = 4x - 7.

Write an equation of the line that passes through (-4,-2) and is parallel to the line

y = 4x - 7.

Step 2: Find b.

y = mx + b

-2 = 4(-4) + b

-2 = -16 + b

+16 +16

14 = b

Step 3: Write equation.

y = 4x + 14

Step 2: Find b.

y = mx + b

-2 = 4(-4) + b

-2 = -16 + b

+16 +16

14 = b

Step 3: Write equation.

y = 4x + 14

Assignment: Pg. 347Assignment: Pg. 347

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5.6Fit a Line of Data

5.6Fit a Line of Data

Example 6The table shows the time needed to roast turkeys of

different weights. Make a scatter plot of the data. Describe the correlation of the data.

Example 6The table shows the time needed to roast turkeys of

different weights. Make a scatter plot of the data. Describe the correlation of the data.

Weight (pounds)

6 8 12 14 18 20 24

Roast time (hours)

2.75 3.00 3.50 4.00 4.25 4.75 5.25

Make a scatter plot of the data. Describe the correlation of the data.

Make a scatter plot of the data. Describe the correlation of the data.

Because the graph rises from left to right, it has a positive correlation

Because the graph rises from left to right, it has a positive correlation

5.6 Fit a Line of Data

5.6 Fit a Line of Data

Step 1: Find the pattern on the data.

- positive correlation - rises from left to right.

- negative correlation - falls from left to right.

- no correlation - no real pattern.

Step 2: Draw line.

half the points above and half the points below.

Step 3: Write equation.

y = mx + b

Step 1: Find the pattern on the data.

- positive correlation - rises from left to right.

- negative correlation - falls from left to right.

- no correlation - no real pattern.

Step 2: Draw line.

half the points above and half the points below.

Step 3: Write equation.

y = mx + b

Assignment: Pg. 348Assignment: Pg. 348

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5.7Predict with Linear Models

5.7Predict with Linear Models

Example 7Use the scatter plot from the example for

Lesson 5.6 above to estimate the time (in hours) it takes to roast a 10 pound turkey.

Step 1: Draw scatter plotStep 2: Draw Line of best fit.Step 3: Find x-coordinate and y-coordinate on

the line.

Example 7Use the scatter plot from the example for

Lesson 5.6 above to estimate the time (in hours) it takes to roast a 10 pound turkey.

Step 1: Draw scatter plotStep 2: Draw Line of best fit.Step 3: Find x-coordinate and y-coordinate on

the line.

Use the scatter plot from the example for Lesson 5.6 above to estimate the time (in hours)

it takes to roast a 10 pound turkey.

Use the scatter plot from the example for Lesson 5.6 above to estimate the time (in hours)

it takes to roast a 10 pound turkey.

It takes about 3.25 hours to cook a 10 pound turkey.

It takes about 3.25 hours to cook a 10 pound turkey.

Assignment: Pg. 348Assignment: Pg. 348

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AssignmentAssignment

Pg. 942 #2-8 even, 22 - 30 evenPg. 942 #2-8 even, 22 - 30 even