13. Suppose you want to use 600 meters of fencing to surround two identical adjacent rectangular
plots. Write a function for the combined area of the plots with respect to the length of one of the
sides (x). What dimensions would produce the maximum combined area? What is that maximum
14. A farmer with 1000 meters of fencing wants to enclose a rectangular plot that borders along a
straight river. If the farmer does not want to fence along the river, what is the largest area that can
be enclosed? What dimensions produce that area?
15. You decide to build a dog run in a back corner your yard. If you only have 60 feet of fencing,
what is the maximum area that you can enclose? What dimensions produce the maximum area?
16. Suppose a stream borders our land, and we want to make a right-triangular garden with the stream as the hypotenuse. If we have only 80 feet of fencing, what is the maximum area of our garden?
What dimensions produce the maximum area?