Swimming pool question

Question

A rectangular swimming pool is twice as long as it is wide. A small concrete walkway surrounds the pool. The walkway is a constant 2 feet wide and has an area of 196 square feet. Find the dimensions of the pool.

Answer 1

W = width of the pool

L = Length of the pool = 2W

Area of the pool is LW = 2W²

 

Length of the outside of the walkway = L + 4 = 2W + 4

Width of the outside of the walkway is W + 4

 

Area of the pool and the walkway is (2W + 4)(W + 4) = 2W² + 12W + 16

Area of the walkway is therefore 12W + 16 = 196

12W = 180

W = 15 and L = 30