Question

The area of a rectangle is 216 square inches. If the perimeter is 60 inches, find the length and width of the rectangle

Answer 1

A=Lw

P=2L+2w

216=Lw

W=216/L...substitute to Perimeter equation

60=2L+2(216/L)

60L=2L^2 + 432

2L^2-60L+432=0

2(L^2 - 30L + 216)=0

2(L-18)(L-12)=0

L=12, W=18 or L=18, W=12