What’s the rate

$35 for 25 taped

explain

I'm confused on this could anyone me and show me what i need to do to solve it.

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle.he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field

In a column proof the right column states your reasons