Warmups

1. Graph y = -3

2. Graph y = 2x - 4

3. Write an equation in standard form: (2,-2) (1,4)

4. Parallel, Perpendicular or neither?

3 4( 1)y x 17

4y x

Perpendicular Lines

Objective: To write an equation of a line perpendicular to another

Perpendicular Lines

How will yesterday change if we want the lines to be perpendicular?? The slope will be opposite sign & reciprocal!!!!

Write an equation in slope-intercept form that passes through the given point and is perpendicular to the given line.

Example 1: (0,4)5

72

y x

Example 2

Write an equation in SLOPE-INTERCEPT form that passes through the given point and is perpendicular to the given line.

y = 2x - 5 (6,4)

Example 3

Write an equation in SLOPE-INTERCEPT form that passes through the given point and is perpendicular to the given line.

2x – 3y = 9 (0,2)

TOO

1. 5x + 4y = 8 (10,5)

2. y = 1/4x – 4 (-2,3)

3. 14x + 2y = 4 (6,4)

43

5y x

4 5y x

1 22

7 7y x

14

4y x

Homework

Pg. 367 # 33-45

Review Chapter 6 part 2

Speaker and Scribe:1 board

1 marker

1 sock

Find the Slope

(3,4)(9, 1) 5

6

(4,1)(9, 2) 3

5

Determine Value of r.

5(4, )( , 2)

3r r m

7r

3(3, )( ,5)

5r r m

8r

Write in STANDARD

( 1, 2)(1,8) 5 3x y

1( 4,6)

2m

2 8x y

Write in POINT-SLOPE

(5,4) 3m 4 3( 5)y x

15 ( 2)3

y x 1(2, 5)

3m

Find x and y intercepts

2 3 12x y (6,0)(0,4)

( 2,0)(0, 8) 4 8y x

Find slope and y-intercept

5 15x y 5, 15m b

2, 5m b 7 2( 1)y x

Parallel, perp. Or neither?

2 3 4x y 10 15 20x y

3 2 6x y 3 2 5x y

2 9y x 1

32

y x

parallel neither Perpendicular