Solve the Problem $$\mathrm { l } = \frac { 1 } { 43 } \mathrm { ft } ; \mathrm { w } = \frac { 13 } { 43 } \mathrm { ft }$$

Solve the problem.
-The length and width of a rectangle must have a sum of 86 feet. Find the dimensions of the rectangle whose area is as large as possible.

A) $$\mathrm { l } = \frac { 1 } { 43 } \mathrm { ft } ; \mathrm { w } = \frac { 13 } { 43 } \mathrm { ft }$$
B) $$\mathrm { l } = 43 \mathrm { ft } ; \mathrm { w } = 129 \mathrm { ft }$$
C) $$\mathrm { l } = 43 \mathrm { ft } ; \mathrm { w } = 43 \mathrm { ft }$$
D) $$\mathrm { l } = 42 \mathrm { ft } ; \mathrm { w } = 44 \mathrm { ft }$$