What is the midpoint of the line segment with endpoints (-5.5, -6.1) and (-0.5,9.1)?

When keisha installed a fence along the 200 foot perimeter of her rectangular back yard, she left an opening for a gate.in the diagram below, she used x to represent the length in feet of the gate? what is the value? a. 10 b. 20 c. 25 d. 30

The formula for the volume of a right square pyramid is given below, where a is the side length of the base and h is the height.

Ineed to know how to write question one in mathematical terms