Answer:
Please see the attached picture for the full solution.
*From the 4th line of the 1st image, you could also expand it using
(a +b)²= a² +2ab +b² and
(a -b)²= a² -2ab +b².
When squaring a fraction, square both the denominator and numerator.
➣(a/b)²= a²/b²
99 because anything less will give you an average of 89 and a decimal
Suppose the dimensions of the rectangle is x by y and let the side enclosed by a house be one of the sides measuring x, then the sides that is to be enclosed are two sides measuring y and one side measuring x.
Thus, the length of fencing needed is given by
P = x + 2y
The area of the rectangle is given by xy,
i.e.

Substituting for y into the equation for the length of fencing needed, we have

For the amount of fencing to be minimum, then

Now, recall that

Thus, the length of fencing needed is given by
P = x + 2y = 24 + 2(12) = 24 + 24 = 48.
Therefore, 48 feets of fencing is needed to enclose the garden.