Question

A rectangular sheet of material has a width that is 6 cm less than its length. The area of the sheet of material is 72 cm². What must be the width of the rectangular sheet?

O 6 cm
O 8 cm
O 12 cm
O 16 cm​

Answer 1

width = 6 cm

Explanation:

Area = width x length

let x = length

width = x - 6

A = 72 cm² = x(x-6) = x² - 2x

rewrite the equation:

x² - 2x - 72 = 0

solve for x by factoring or the quadratic equation:

(x-12)(x+6) = 0

x = 12, -6

therefore x = length = 12

Width = 12 - 6 = 6