The width of a painting is 4 inches less than the length, and the surface area is 320 square inches. Find the length.

Question

Mathematics

Jocelynn Pratt

7 April, 00:44

The width of a painting is 4 inches less than the length, and the surface area is 320 square inches. Find the length.

+1

Answers (2)

Know the Answer?

Aleena Hood · Answer 1

The length is 20 inches. 20 times 16 equals 320 so the length is 20 inches and the width is 16.

Myles Richardson · Answer 2

320 = L * (L - 4)

320 = L^2 - 4l

L^2 - 4L - 320

Use quadratic formula

W = (-b + - sqrt (b^2 - 4ac)) / 2a

W = - 20 and 16

The width can't be negative so width = 20inches