Three of these are wrong. Find the one that holds.

Exercise and reference answers

Questions

1. Question

   Three of these statements about slope are false.

   Choices

   1. Item

      A vertical line has undefined slope

      Correct

      Yes

   2. Explanation

      Zero slope belongs to HORIZONTAL lines.

      Item

      A vertical line has slope zero

   3. Explanation

      Its slope is zero, not undefined.

      Item

      A horizontal line has undefined slope

   4. Explanation

      Their slopes multiply to −1.

      Item

      Perpendicular lines share a slope

Explanation