A farmer has units of fence. If he uses this to build a square fence, what will be the area enclosed by the fence?
(correct answer)
Explanation: Since we are looking at a square, the formula for the area of a square is .
Therefore we need to know the length of each side.
Since this is a square fence, then each of the four sides will be equal.
The amount of fence that the farmer has in the problem will become the perimeter of our square.
Since
when working with a square, for this problem
.
Plug that into our original equation.