What is the slope of the line x=-2?

1 Answer
Mar 21, 2018

Slope = Undefined

Explanation:

If a line has the equation #x=k#, where #k# is a constant, it is a vertical line. A vertical line has an undefined slope.

PROOF:
The equation for slope is #(y_1-y)/(x_1-x)#. If the equation is #x=-2#, we can substitute this value into #(y_1-y)/(x_1-x)# to get #(y_1-y)/(-2-(-2)#, and simplifying this equation makes the denominator #0#, which is undefined.