1. Parallel and Perpendicular

2. These lines have the same slope (the same m) Ex: y=4x+2 y=4x-8
Parallel Lines
These lines have the same slope (the same m)
Ex: y=4x y=4x-8

3. The slopes are completely flipped (Opposite reciprocal).
Perpendicular
The slopes are completely flipped (Opposite reciprocal).
Ex: y=5x y=− 1 5 x+2

4. Writing Parallel and Perpendicular equations
y= 3 4 x+5
Parallel: y= 3 4 x+[not 5]
Perpendicular: y= 4 3 x+5

5. Example 3
A line passes through the point (12,5) and is parallel to the graph of y= 2 3 𝑥−1. Write your answer in slope-intercept form.
y-5= 2 3 (x-12)
y-5= 2 3 x-8
y= 2 3 x-3

6. A line passes through the point (12,5) and is perpendicular to the graph of y= 4 7 𝑥−8. Write your answer in slope- intercept form.
y-5=− 7 4 (x-12)
y-5=− 7 4 x+21
y=− 7 4 x+26

7. Assignment
Page 135
# 1-6, 14, and 35
# 7-12, 20-25