Jane is going to fence her backyard. she purchased 120 feet of fencing and knows that she wants to fence in a rectangular area where one side will be the back of her house. she knows her house is 25 feet across the back. which of the following is the equation that jane can use to figure out how far back from the house she can fence in? a) 25(x + 25 ) = 120 b) x + 25 = 120 c) 25x = 120 d ) x + x + 25 = 120