Draw the pool (one rectangle) and the surrounding deck (another, bigger, rectangle around the first one).

Since you haven't shown any work, I don't know what method you're supposed to be using to solve this exercise. But I'll guess that you know how to solve quadratics.

So label the width of the decking as "x". What then is the expression for the total area of the pool-and-deck area? Set this equal to the given area, and solve for "x".

If you get stuck, please reply showing all of your steps.

Thank you.

Eliz.