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Algebra Chapter 5: LINEAR FUNCTIONS Name:______________________________ Teacher:____________________________ Pd: _______

Name Date Ms - White Plains Middle School · Table of Contents Day 1 - Chapter 5-3/5-4: Slope SWBAT: Calculate the slope from any two points Pgs. #1 - 5 Hw pgs. #6 – 7 Day 2 - Chapter

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Page 1: Name Date Ms - White Plains Middle School · Table of Contents Day 1 - Chapter 5-3/5-4: Slope SWBAT: Calculate the slope from any two points Pgs. #1 - 5 Hw pgs. #6 – 7 Day 2 - Chapter

Algebra

Chapter 5: LINEAR FUNCTIONS

Name:______________________________

Teacher:____________________________

Pd: _______

Page 2: Name Date Ms - White Plains Middle School · Table of Contents Day 1 - Chapter 5-3/5-4: Slope SWBAT: Calculate the slope from any two points Pgs. #1 - 5 Hw pgs. #6 – 7 Day 2 - Chapter

Table of Contents

Day 1 - Chapter 5-3/5-4: Slope SWBAT: Calculate the slope from any two points

Pgs. #1 - 5

Hw pgs. #6 – 7

Day 2 - Chapter 5-6: Slope – Intercept Form SWBAT: Write and Graph a linear equation in Slope – Intercept Form

Pgs. #8 – 11

Hw pgs. #12 – 14

Day 3 - Chapter 5-7: Point - Slope Form SWBAT: Write and Graph a linear equation in Point - Slope Form

Pgs. #15 – 19

Hw pgs. #20 – 21

Day 4 - Chapter 5-6/5-7: Vertical and Horizontal Lines

SWBAT: Write and Graph Vertical and Horizontal Lines

Pgs. #22-25

Hw pgs. #26-27

Day 5 - Review: Sections 5-2 through 5 - 7 Pgs. #28-31

Day 6 - Chapter 5-8: Slopes of Parallel and Perpendicular Lines SWBAT: Calculate the slope of Parallel and Perpendicular Lines

Pgs. #32-37

Hw pgs. #38-39

Day 7 - Chapter 5-8: Equations of Parallel and Perpendicular Lines SWBAT: Write the equation of Parallel and Perpendicular Lines

Pgs. #40-43

Hw pgs. #44-45

Day 8 - Chapter 5-5: Direct Variation SWBAT: Identify, write, and graph direct variations

Pgs. #46-50

Hw pgs. #50-51

Day 9 – 10: Review of Chapter 5 SWBAT: Graph and Write Linear Equations

Pgs. #52-66

Page 3: Name Date Ms - White Plains Middle School · Table of Contents Day 1 - Chapter 5-3/5-4: Slope SWBAT: Calculate the slope from any two points Pgs. #1 - 5 Hw pgs. #6 – 7 Day 2 - Chapter

1

Day 1 – Slope

Warm - Up

Find the x- and y- intercepts.

a. b.

x-intercept: _______________ x-intercept: _______________

y-intercept: _______________ y-intercept: _______________

Motivation:

The slope of a line measures the steepness of the line.

We’re familiar with the word slope as it relates to mountains.

Skiers and snowboarders refer to “hitting the slopes.”

Slope measures the ratio of the change in the y-value of a line to a

given change in its x-value.

Finding Slope

DEFINITION OF SLOPE

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2

Example 1: Calculating the slope from a Graph

a: Find the slope of the line. b: Find the slope of the line.

1st Point: _________ 2

nd Point: ________ 1

st Point: _________ 2

nd Point: _________

2 1

2 1

slopeY Y

X X

ym

x

2 1

2 1

slopeY Y

X X

ym

x

c: Find the slope of the line. d: Find the slope of the line.

1st Point: _________ 2

nd Point: _________ 1

st Point: ________ 2

nd Point: _________

2 1

2 1

slopeY Y

X X

ym

x

2 1

2 1

slopeY Y

X X

ym

x

x

y

x

y

x

y

x

y

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3

e. f.

Example 2: Calculating the slope from a set up points

a) Find the slope of the line that passes through the points 8, 7 and 4, 5 .

2 1

2 1

Y Y

X Xm

and

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4

and

b) Find the slope of the line that passes through the points (4, 3) and (–5, –2).

2 1

2 1

Y Y

X Xm

c) Find the slope of the line that passes through the points (–4, –7) and (–3, –5).

2 1

2 1

Y Y

X Xm

Example 3: Calculating the Slope from a Table of Values

a) Find the slope of the line that contains the points from the table

b) Find the slope of the line that contains the points from the table

and

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5

Challenge

Summary

Exit Ticket

1. Fill in the blanks.

2.

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6

Day 1 – Homework

Slope

1) Find the slope of the line that passes through each of the following sets of points.

(a) (b) (c)

(d) (e) (f)

2) Find the slope of each of the following lines graphically:

a) fkdjflkdjfjkd b)

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7

c) d)

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8

Day 2 - Slope – Intercept Form

Warm Up

Motivation:

Who uses this?

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9

Graphing by using slope and y-intercept

1. 24

3 xy m = ______ 2. 42 xy m = ______

y-intercept = b = (0, ____ ) y-intercept = b = (0, ____ )

Practice

Graphing by using slope and y-intercept

3. 32

1 xy m = ______ 4. xy 3 m = ______

y-intercept = b = (0, ____ ) y-intercept = b = (0, ____ )

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10

5.

Writing Equations of Graphs

9. Write the equation in slope–intercept form. Then graph the line described by the equation.

3x + 2y = 5

6. 7. 8.

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11

10. Write the equation in slope–intercept form. Then graph the line described by the equation.

4x - 2y = 14

Challenge

SUMMARY

Exit Ticket

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12

Day 2 – Homework

Slope – Intercept Form

1) Which of the following lines has a slope of 5 and a y-intercept of 3 ?

(1) 5 3y x (3) 3 5y x

(2) 5

3y x (4) 3 5y x

2) Which of the following equations represents the graph shown?

(1) 3

32

y x (3) 2

33

y x

(2) 3

22

y x (4) 2

23

y x

3) Graph each line.

(a) y = –3x+ 2 (b) y = 1

2 x

y

x

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13

(c) y = 6x + 3 (d) y = 2

3x + 9

(e) y = –x + 2 (f) y = x - 3

(g) y = -

x - 4 (h) y = 2x + 7

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14

1) Write an equation of each line in slope – intercept form. Identify the slope and y-intercept.

a. 2 2 4x y b. 5 7x y

c. 6x + 2y = 8 d. 10 5 15y

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15

Day 3 – Point Slope Form

Warm – Up

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16

Yesterday, we learned how to graph equations using the slope and the y-intercept. Today we are

going to write equations of lines.

First, let’s see how to use the equation.

Example 1: Graph the linear equation.

y – 1 = 2(x – 3) m = _______ pt = ( ___, ____ ) Practice: Graph the linear equation.

y + 4 = -¼(x – 8) m = _______ pt = ( ___, ____ )

Equations of Lines

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17

Example 2: Converting Point-Slope to Slope-Intercept Form and Standard Form.

Write in Slope-Intercept form and Standard Form.

Practice: Converting Point-Slope form to Slope intercept Form

Writing Equations of Lines

Example 3: Write the equation of a line given the slope and a point.

(-3, -4); m = –3

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18

Practice: Write the equation of a line given the slope and a point.

(1, 2); m = –3

Example 4: Write the equation of a line passing through the two points given.

(10, 20) and (20, 65)

Step 1:

Step 2: plug m, and point into equation.

y – y1 = m(x – x1)

Practice: Write the equation of a line passing through the two points given.

(2, –5) and (–8, 5)

Step 1:

Step 2: plug m, and point into equation.

y – y1 = m(x – x1)

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19

Challenge

Write the equation of a line in point-slope form passing through the two points given.

(f, g) (h, j)

SUMMARY

Exit Ticket

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20

Day 3 – Point Slope Form - HW

1) Which equation describes the line through (–5, 1) with the slope of 1?

(a) y = x – 6 (c) y = –5x + 6

(b) y = –5x – 6 (d) y = x + 6

2) A line contains (4, 4) and (5, 2). What is the slope and y – intercept?

(a) slope = –2; y – intercept = 2 (c) slope = –2; y – intercept = 12

(b) slope = 1.2; y – intercept = –2 (d) slope = 12; y – intercept = 1.2

Write an equation for the line with the given slope and point in slope-intercept form.

3) slope = 3; (–4, 2)

Equation: ______________________

4) slope = –1; (6, –1 )

Equation: ______________________

5) slope = 0; (1, –8)

Equation: ______________________

6) slope = –9; (–2, –3)

Equation: ______________________

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21

Write an equation for the line through the two points in slope intercept form.

7) (2, 1); (0, –7)

Equation: ______________________

8) (–6, –6); (2, –2)

Equation: ______________________

9) (–2, –3); (–1, –4)

Equation: ______________________

10) (6, 12); (0, 0)

Equation: ______________________

Write an equation for the line for each graph.

11) 12)

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22

Day 4 – Vertical and Horizontal Lines

Warm – Up:

Horizontal Lines Picture:

Slope =

If your point is (a, b), then your equation is always y = ____

Ex: Write the equation of the horizontal line passing through each point.

1. (3, 7)

2. (2, -4) 3. (8, 0)

4.

5. 6.

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23

Vertical Lines Picture:

Slope =

If your point is (a, b), then your equation is always x = ____

Ex: Write the equation of the vertical line passing through each point.

7. (2, 9)

8. (1, -3) 9. (0, 10)

10.

11. 12.

Parallel Lines

Parallel Lines have the _______ slope What can you say about all horizontal lines?

Page 26: Name Date Ms - White Plains Middle School · Table of Contents Day 1 - Chapter 5-3/5-4: Slope SWBAT: Calculate the slope from any two points Pgs. #1 - 5 Hw pgs. #6 – 7 Day 2 - Chapter

24

What can you say about all vertical lines? What can you say about a horizontal line and a vertical line?

Write the equation of the line…..

13. Parallel to y = 4, through (2, -3)

14. Parallel to x = -3, through (1, 2)

15. Parallel to the y-axis through (2, 4)

16. Parallel to the x-axis through (3, -5)

17. Through (2, 8) with a slope of 0.

18. Through (3, 3) with an undefined slope.

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25

Write the slope-intercept form of the equation of the line through the given points.

1) through: (5, -2) and (0, -2) 8) through: (-6, -1) and (-6, 11)

Challenge Write the equation of a line perpendicular to y = 1, passing through (2, 10). SUMMARY Memory Device for Vertical Lines Memory Device for Horizontal Lines

x = “a” value of point = (a, b) y = “b” value of point = (a, b)

Exit Ticket

1.

2.

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26

Day 4 - HW

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27

13) Write the equation of a line parallel to x = 12 passing through the point (4, 5).

14) Write the equation of a line parallel to y = 1 passing through the point (-3, 7).

15) Write the equation of a line parallel to the x-axis passing through the point (1, 1).

16) Write the equation of a line parallel to the y-axis passing through the point (-8, 0).

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28

Day 5 – Review of Sections 5-2 through 5-6

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29

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30

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31

Write the equation of the lines below. Write your answer in slope-intercept form.

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32

Day 6 – Slopes of Parallel and Perpendicular Lines

Warm Up

Directions: Find the reciprocal.

1) 2 2) 3

1 3)

9

5

Directions: Find the slope of the line that passes through each pair of points.

4) (2, 2) and (–1, 3) 5) (3, 4) and (4, 6) 6) (5, 1) and (0, 0)

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33

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34

Page 37: Name Date Ms - White Plains Middle School · Table of Contents Day 1 - Chapter 5-3/5-4: Slope SWBAT: Calculate the slope from any two points Pgs. #1 - 5 Hw pgs. #6 – 7 Day 2 - Chapter

35

Example 3:

Graph a line parallel to the given line and passing through the given point.

Graph a line perpendicular to the given line and passing through the given point.

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36

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37

Challenge

If ||PQ RS and the slope of 1

4

xPQ

and the slope of RS is

6

8, then find the value of x. Justify

algebraically or numerically.

SUMMARY

Exit Ticket

1.

2.

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38

Day 6 – Slopes of Parallel and Perpendicular Lines HW

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39

7)

8)

9)

10)

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40

Day 7 – Equations of Parallel and Perpendicular Lines

Warm Up

Determine the equation of the line that passes through the two points 2,4 and 8,0 .

1) Write an equation for the line that passes through (4, 10) and is parallel to the line described by y = 3x + 8.

Step 1: m = _____

Step 2: plug in the point into y – y1 = m(x – x1) and solve for y.

Equation: __________________________________

2) Write an equation for the line that passes through (–2 , 5) and is parallel to the line described by y = 2

1x – 7.

Step 1: m = _____

Step 2: plug in the point into y – y1 = m(x – x1) and solve for y.

Equation: __________________________________

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41

3) Write an equation for the line that passes through (2, –1) and is perpendicular to the line described by

y = 2x – 5.

Step 1: m = _____

Step 2: plug in the point into y – y1 = m(x – x1) and solve for y.

Equation: __________________________________

4) Write an equation for the line that passes through (2, 6) and is perpendicular to the line described by

y = -3

1x + 2.

Step 1: m = _____

Step 2: plug in the point into y – y1 = m(x – x1) and solve for y.

Equation: __________________________________

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42

Regents Practice

5) What is the slope of a line parallel to the line whose equation is y = -4x + 5?

6) What is the slope of a line parallel to the line whose equation is 3x + 6y = 6?

7)

8) Kjk

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43

Challenge

SUMMARY

Exit Ticket

1.

2.

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44

Day 7 – Equations of Parallel and Perpendicular Lines - HW

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45

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46

Day 8 – Direct Variation

Warm Up

Find the slope of the linear function represented by the table below.

1)

2)

Motivation:

Who uses this?

A recipe for paella calls for 1 cup of rice to make 5 servings. In other words, a chef

needs 1 cup of rice for every 5 servings.

The equation y = 5x describes this relationship. In this relationship, the number of

servings varies directly with the number of cups of rice.

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47

Direct Variation

Example1: Identifying Direct Variations from an Equation

Tell whether the equation represents a direct variation. If so, identify the constant of

variation.

1) y = 21x 2) 3x + y = 8

Direct Variation? _____________ Direct Variation? ____________

Constant of Variation: ___________ Constant of Variation: __________

3) –4x + 3y = 0 4) 3x + 0 = 15y

Direct Variation? _____________ Direct Variation? ____________

Constant of Variation: ___________ Constant of Variation: __________

What happens if you solve y = kx for k?

Let’s see…

In a direct variation, the ratio ________

is equal to the constant of variation.

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Example 2: Identifying Direct Variations from Ordered Pairs

Tell whether the relationship is a direct variation. Explain.

5) 6)

Find y

x for each ordered pair. Find

y

x for each ordered pair.

Direct Variation? _____________ Direct Variation? ____________

Constant of Variation: ___________ Constant of Variation: __________

Example 3: Identifying Direct Variations from a Graph

Tell whether the relationship is a direct variation. Explain.

7) 8)

Direct Variation? _____________ Direct Variation? ____________

Constant of Variation: ___________ Constant of Variation: __________

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Example 4: Writing and Solving Direct Variation Equations

9) The value of y varies directly with x, and y = 3 when x = 9. Find y when x = 21.

Use a proportion: 9

3

x

y

10) The value of y varies directly with x, and y = 4.5 when x = 0.5. Find y when x = 10.

Challenge

SUMMARY

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50

Exit Ticket

Day 8 – Homework

Direct Variation

Tell whether each equation is a direct variation. If so, identify the constant of variation.

2) y = 3x 3) y = 2x – 9

3) 2x + 3y = 0 4) 3y = 9x

Find the value of y

xfor each ordered pair. Then tell whether the relationship is a direct variation.

5) 6) 7)

________________ _________________ _________________

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Tell whether each graph is a direct variation. If so, identify the constant of variation.

8) 9)

_______________ ________________

10) The value y varies directly with x, and y = –18 when x = 6. Find y when x = –8.

11) The value of y varies directly with x and y = ½ when x = 5. Find y when x = 30.

12)

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Chapter 5: Review of Linear Functions

Section 1: Slope

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Section 2: X and Y – Intercepts

9. Find the x-intercept and the y-intercept for each of the following:

a. 3x + y = 6 b. -2x – 4y = -8

10. Find the x-intercept and the y-intercept for each of the following:

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Section 3: Direct Variation

11.

12.

13. Tell whether each is a direct variation. If yes, identify the constant of variation?

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14.

15.

SECTION 4: Writing Equations of Lines

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16. 17. 18.

19. 20. 21.

22. 23.

24. 25.

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26. 27.

28. 29.

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Graph Each Vertical and/or Horizontal Line.

30. x = 3 31. x = -2

32. y = 4 33. y = -3

34. 35.

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Applications

36. The graph below shows the relationship between the number of miles driven and the cost of

Super-City’s taxi fare.

Part A

Write an equation show the relationship between the number of miles driven and the cost of

Super-City’s taxi fare.

Equation: __________________

Part B

What is the taxi fare for being driven 15 miles?

Answer: __________________ dollars

Super – City Taxi Fare

1 2 3 4 5 6 7 8 9 10 0

$2

$4

$6

$8

$10

$12

$14

$16 C

ost

(doll

ars)

t

Number of Miles Driven

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37. The accompanying graph represents the yearly cost of joining a Sports Club.

Part A

Write an equation show the relationship between the number of months and

the yearly cost.

Equation: __________________

Part B

What is the total cost of joining the club and attending 10 months during

the year?

Answer: _______________ dollars

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38. An online video store rents movies for $2.00 per video plus a $5.00 membership fee.

Part A

Write an equation to represent the cost of renting a video in relationship to the number of videos rented.

Equation: _____________________________

Part B

Make a table of values to represent your equation in part A.

Number of Videos Cost

($)

Part C

Graph your equation using your table of values.

Part D

Use the graph to determine the cost for renting 6 videos.

Answer: __________________ dollars

2

4

6

8

10

12

14

16

18

20

0 1 2 3 4 5 6

Number of videos

Cost for Video Rentals

Cost ($)

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39. Mrs. Jackson will need a babysitter for her infant baby. She decides to offer $20 for

travel plus $5 per hour worked.

Part A

Write an equation to represent the cost for a babysitter in relationship to the number of hours worked.

Equation: _____________________________

Part B

Make a table of values to represent your equation in part A.

Number of Hours Cost

($)

Part C

Graph your equation using your table of values.

Part D

Determine the cost of hiring a babysitter for 10 hours.

Answer: __________________ dollars

Number of Hours

$ C

ost

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40. m = -4, (-2, -8)

41.

42.

43.

44.

45.

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Section 5: Parallel and Perpendicular Lines

46. 47.

48. 49.

50. 51.

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52. 53.

54. 55. Parallel to x = -2, through (-12, 0)

56. 57. Perpendicular to y = -5, through (1, -2)

58. 59. Parallel to x-axis, through, (3, 8)

(-6, 8)

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Draw a line parallel to the given line below passing through given point.

60. 61.

Draw a line perpendicular to the given line below passing through given point.

62. 63.

Line1

Line1

Line1

Line1