1. Geometry 3-6 Parallel and Perpendicular Lines
Parallel lines have the exact same slope (sign and number) but different y-intercepts. Example: y = -2x + 3 and y = -2x – 1 are parallel y = 3x + 3 and y = -3x – 1 are not parallel Example) Are the lines 3x + 2y = 1 and -5y = 10x -5 parallel?

2. Perpendicular lines have flipped sign, flipped fraction slopes
Perpendicular lines have flipped sign, flipped fraction slopes. Example: y = -2/3x + 3 and y = 3/2x – 1 are perp. y = 4/5x + 3 and y = 5/4x – 1 are not perp. y = 6/7x + 3 and y = -6/7x – 1 are not perp. Example) Are the lines 3x + 7y = 14 and 6y = 14x – 12 perpendicular?

3. Examples What line is parallel to y=4x -1 with a y-intercept of 5?
What line is perpendicular to y = 2/5x – 2 with y-intercept 1?

4. What line is parallel to the given line? Perpendicular?
A) y = 4/3x + 1
B) y = 3/4x + 2
(-3, 3)
C) y = -4/3x + 3
D) y = -3/4x + 4
(3, -5)