The porch is 8 by 40.
Work Step by Step
Note, the 5 step process is as follows: (1) Familiarize yourself with the problem. (2) Translate the problem into Algebra. (3) Solve. (4) Check. Note, if we want to check a solution, we would plug it back into the equation and check that the equation yields a true statement. (5) State the answer. After becoming familiar with the problem, we find: $$320=(w)(5w) \\ 320 = 5w^2 \\ w=8\\ So: \\ l=5(8)=40$$ The porch is 8 by 40.