I need help figuring out allies radical equations. The question below is an example I am trying to figure out.

You work for an outdoor landscaping company and a customer wants to add a pool to their back yard. The pool will be twice as long as it is wide and is surrounded by a walkway of uniform width of _ ft. The combined area of the pool and the walkway is 25 3 square feet. What will the dimensions of the pool be? (HINT: start with a drawing) What will the overall dimensions of the pool and walkway be