1. What is the slope of a line that is perpendicular to the x-axis

The slope of a line that is perpendicular to the x-axis is undefined.

Step-by-step explanation:

We know that the x-axis is a horizontal line.

Therefore, the slope of a line that is perpendicular to the x-axis is undefined.

For example, the slope between (1, 2) and (1, 4) is:

Using the slope formula

Slope = m =  [y₂ - y₁] /  [x₂ - x₁]

                 = [4 - 2] / [1 - 1]

                  = 2 / 0

                  = ∞

we need the options

step-by-step explanation: