Set 1: Linear Functions (Intermediate)

**Choice B is the best answer.** Horizontal lines have slope 0

Explanation

Answer: B

PROBLEM

What is the slope of a horizontal line?

-1

✓ Correct

undefined

Detailed Explanation

Choice B is the best answer. Horizontal lines have slope 0

Why others are wrong:

A: -1 is incorrect because it does not satisfy the equation.

C: undefined is incorrect because it does not satisfy the equation.

D: 1 is incorrect because it does not satisfy the equation.