the length of a rectangular frame is 5 cm more than the width. the area inside the frame is 66 square cm. find the width of the frame.

1 answer

L = W + 5

A = L * W

( W + 5 ) * W = 66

W ^ 2 + 5 W = 66

W ^ 2 + 5 W - 66 = 0

Solutions of equation are :

W = - 11

and

W = 6

Length can't be negative so :

W = 6 cm

Proof:

L = W + 5 = 6 + 5 = 11

A = L * W = 11 * 6 = 66 cm ^ 2