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Identify the slope and y-intercept of each equation.1. Y = -6x2. Y = 3x – 73. 4x – y = 54. 7x – 3y = 4

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Identify the slope and y-intercept of each equation.1. Y = -6x2. Y = 3x – 73. 4x – y = 54. 7x – 3y = 4

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WARM UP

Identify the slope and y-intercept of each equation.1. Y = -6x2. Y = 3x – 73. 4x – y = 54. 7x – 3y = 4

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WARM UP

Identify the slope and y-intercept of each equation.1. Y = -6x2. Y = 3x – 73. 4x – y = 54. 7x – 3y = 4

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WARM UP

Identify the slope and y-intercept of each equation.1. y = -6x2. y = 3x – 73. 4x – y = 54. 7x – 3y = 4

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WARM UP

Identify the slope and y-intercept of each equation.1. Y = -6x2. Y = 3x – 73. 4x – y = 54. 7x – 3y = 4

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4.7 Graphing Lines Using Slope-Intercept Form

CLASS SCHEDULE UNTIL BREAK:12/9 -12/12: Graphing Lines using Slope-Intercept Form12/13: Quiz12/16-12/17: Functions and Relations12/18: Chapter 4 review12/19: Chapter Four Test12/20: Catch-up day or Christmas Graphs.

4.7 Graphing Lines Using Slope-Intercept Form

Today’s Schedule:•Lesson 4.7 Powerpoint•In class assignment/homework•Exit SlipGOAL: Graph a linear equation in slope-intercept form.KEY WORDS: slope, y-intercept, slope-intercept form, parallel lines.

4.7 Graphing Lines Using Slope-Intercept Form

SLOPE-INTERCEPT FORM OF THE EQUATION OF A LINE

The linear equation y = mx + b is written in slope-intercept form, where m is the slope and b is the y-intercept.

y = mx + b

slopey-intercept

4.7 Graphing Lines Using Slope-Intercept Form

EXAMPLE 3 Identify Parallel Lines

Which of the following lines are parallel?Line a: -x + 2y = 6 line b: -x + 2y = -2 line c: x + 2y = 4

1 Rewrite each equation in slope-intercept form.

Line a: y = ½x + 3 line b: y = ½x - 1 line c: y = -½x + 2

4.7 Graphing Lines Using Slope-Intercept Form

EXAMPLE 3 Identify Parallel Lines

Which of the following lines are parallel?Line a: -x + 2y = 6 line b: -x + 2y = -2 line c: x + 2y = 4

2 Identify the slope of each equation.

Line a: slope is ½ line b: slope is ½ line c: slope is -½

4.7 Graphing Lines Using Slope-Intercept Form

EXAMPLE 3 Identify Parallel Lines

Which of the following lines are parallel?Line a: -x + 2y = 6 line b: -x + 2y = -2 line c: x + 2y = 4

3 Compare the slopes.

Lines a and b are parallel because each has a slope of ½.

Line c is not parallel to either of the other two lines because it has a slope of -½.

CHECK √ The graph gives you a visual check.

4.7 Graphing Lines Using Slope-Intercept Form

Practice: Are the following lines parallel?line a: 3x + 2y = 6 line b: 6x +4y = 6

Sí, paralelo!Tu’ estas certificada!

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PARALLEL LINES Determine whether the graphs of the two equations are parallel. Graph the lines and explain

your answer.1. Line a: y = -3x + 2 Line b: y + 3x = -42. Line a: 2x – 12 = y Line b: y = 10 + 2x3. Line a: y = x + 8 Line b: x – y = -14. Line a: 2x – 5y = -3 Line b: 5x + 2y = 65. Line a: y + 6x = 8 Line b: 2y = 12x – 46. Line a: 3y – 4x = 3 Line b: 3y = -4x + 9

GRAPH THESE LINES Put the equation in slope intercept form (y = mx + b) and graph.

7. Y = 2x + 4

8. Y = - x -2

9. Y = - + 3

10. Y = x - 4

1 2 3 4

4 3

11. -x + y = 5

12. y – 3x = -3