First you want to subtract 36
so it looks like this ![\sqrt[4] {(4x+164)^3}=64](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%20%7B%284x%2B164%29%5E3%7D%3D64)
Then you want to cancel out the square root 4 by raising that to the 4th power (you must do this to both sides)
which is equal to 
Then you take the cube root to both sides [tex]\sqrt[3]{(4x+164)^3}=\sqrt[3]{16777216}[tex]
Then you end up with the equation 4x+164=256
Then subtract 164 to both sides
4x=92
then divide 92 by 4
Then you get x=23
We will need to find the area of the circle. We will use this formula:
A =

* radius^2
The question says we will use 3.14 for

.
And we know radius is equal to 22.
A = 3.14 * 22^2
A = 3.14 * 484
A = 1519.76
Round to the nearest tenth.
A = 1519.8
So, the maximum area the sprinkler can water is <span>1519.8</span> ft squared.
EDIT:
I found a mistake in my answer.
(x-6)(x+2)
When you foil it you get x^2+2x-6x-12
After you do this you then add like terms to get x^2-4x-12
Therefore the answer (x-6)(x+2) is correct.