True or false: parallel and perpendicular

Exercise and reference answers

Questions

1. Statement is true

   Yes

   Statement

   Two lines are parallel if and only if their slopes are equal.

2. Statement is true

   Yes

   Statement

   Two lines are perpendicular if and only if their slopes multiply to −1.

3. Statement is true

   No

   Statement

   Perpendicular lines have equal slopes.

4. Statement is true

   No

   Statement

   Parallel lines have slopes multiplying to −1.

5. Statement is true

   Yes

   Statement

   Three points are collinear when slope AB equals slope BC.

Explanation