Question

You are resurfacing your backyard pool. The pool is in the shape of a rectangular prism with a length of 20 ft, a width of 10 ft, and a depth of 4 ft. How many square feet of the resurfacing paint will you need?

Answer 1

Answer:

$440\ ft^2$

Step-by-step explanation:

we know that

The area of the backyard pool to be resurfaced is equal to the area of the base plus the area of its four lateral sides.

so

$A=B+PH$

where

B is the area of the base

P is the perimeter of the base

H is the depth of the pool

Find the area of the base B

$B=(L)(W)$

substitute the given values

$B=(20)(10)=200\ ft^2$

Find the perimeter of the base P

$P=2(L+W)$

substitute the given values

$P=2(20+10)=60\ ft$

we have

$H=4\ ft$

Find the area of the backyard pool to be resurfaced

$A=B+PH$

substitute the values

$A=200+60(4)$

$A=440\ ft^2$