Question

Explain how slope can help you determine whether lines are parallel or perpendicular.

Answer 1

Parallel lines always have equal slopes

example:
y = 3x+5
y = 3x+7
are parallel with slopes equal to 3. The y intercepts are different meaning that these lines will never cross

Answer 2

perpendicular slopes always multiply to -1

Example:
y = 5x + 10
y = -0.2x - 12

the slopes 5 and -0.2 multiply to -1. So these lines are pependicular

Answer 3

perpendicular means that a right angle, or a 90 degree angle, is formed where the two lines meet