Having a $75 added cost to the total price, we can presume they will never equal. It is easy to see if you make it algebraic:

They will never equal each other.
Answer:
9.72
Step-by-step explanation:
Because the two vertices have the same x-coordinate, the side is a vertical line. It starts vertically from -18 to 18
the length = 18 - (-18)
the length = 18 + 18
the length = 36
The length of the side is 36 unit