Among All Rectangles Having a Perimeter of 24m, Find the Dimensions

Multiple Choice

Among all rectangles having a perimeter of 24m, find the dimensions of the one with the largest area.

A) $9 \mathrm {~m} \text { by } 15 \mathrm {~m}$
B) $\frac { 9 } { 4 } \mathrm {~m} \text { by } \frac { 15 } { 4 } \mathrm {~m}$
C) $4 \mathrm {~m} \text { by } 6 \mathrm {~m}$
D) $6 \mathrm { mby } 6 \mathrm {~m}$
E) $\frac { 9 } { 2 } \mathrm {~m} \text { by } \frac { 15 } { 2 } \mathrm {~m}$