You are building a concrete deck around a rectangular swimming pool. The pool is three times as long as it is wide. The deck will have a constant width of four feet. In order to have enough concrete, you have calculated the area of the deck to be 832 square feet.

Question

You are building a concrete deck around a rectangular swimming pool. The pool is three times as long as it is wide.  The deck will have a constant width of four feet.  In order to have enough concrete, you have calculated the area of the deck to be 832 square feet.
What are the dimensions of the pool?

I really do not know how to do this. I am extremely confused and need help. If anyone could please help me that would mean a lot to me! I am stressing over this and confused. Again, I would appreciate help a lot! Thank you. Also, there are no answers or choices that come with this.

Steve · Answer

If the width of the pool is w, then the length is 3w.

So, the difference in area between the whole thing and just the pool is the area of the deck: 832

(w+8)(3w+8) - w(3w) = 832
w = 24

So, the pool is 24x72 feet

Check:
The pool+deck has area (24+8)(72+8) = 2560
The pool has area 24*72 = 1728

2560-1728 = 832

Tia · Answer

Wow, thank you so much! My parents aren't here to help me so you did so much! :) I understand how you did 3w and from there on it all made sense. If only I used variables. Thank you so much!

Steve · Answer

aw, shucks... <scuff scuff>