16+4(c-5)=220 what is c

Me asap! what is the slope of this line? enter your answer in the box.

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

4+(2+x) can you me solve this problem