Identify the line with an undefined slope

Answer:
d. vertical line
Step-by-step explanation:
A line with an undefined slope is a vertical line
Slope is the change in y over the change in x
When the slope is undefined, it means that the x does not change, which is a vertical line
Answer:
Line D
Step-by-step explanation:
Slope is defined as rise/run. Since a vertical line has zero run and infinite rise the equation is infinity/0 and anything divided by zero is undefined.