1. Perpendicular Lines in the Coordinate Plane
Chapter 3 Section 3.7
Perpendicular Lines in the
Coordinate Plane

2. Warm-Up
Line m is perpendicular to line n. If line m has a positive slope, what kind of slope does line n have?
Find the slope of the line that passes through
the points (5, 6) and (-9, 0).

3. How Are Perpendicular Lines Related?
Postulate 18: The product of their slopes is –1.
Vertical and horizontal lines are perpendicular
Determine if the lines are perpendicular

4. The Slopes of Two Lines Are Given. Are They Perpendicular?

5. Decide Whether p1 and p2 are Perpendicular

6. Decide Whether p1 or p2 Are Perpendicular