Dog Pen - Jill has decided having a pen with the maximum area might not be best. After all, the bigger the pen, the more it
will be to clean it. She now thinks that 20,000 square feet is
the best possible area for a dog pen. She is still using a total of
500 feet of fencing in addition to the side of the house.
Write an equation whose solution will give the distance the pen
should extend out from the house.
Solve your equation and explain your results.