A rectangle with an area of 120 i n^2 has a length 8 inches longer than two times its width. What is the width of the rectangle?

1 Answer
Jul 1, 2016

6 inches

Explanation:

Area of a rectangle with length, l and breadth, b = l*b

Given l = 2b + 8 and A = 120

Area A = l* b = (2b + 8)*b = 2b^2 + 8b = 120 =>

2b^2 + 8b - 120 = 0 =>

b^2 + 4b - 60 = 0 =>

b^2 + 10b - 6b - 60 = 0 =>

b(b+10) -6 (b+10) = 0 =>

(b-6)(b+10) = 0; => b = 6 as b cannot be -10.

Width is 6 inches