Answer:
length = 12 feet and width = 8 feet
Explanation:
since the area = 96 ft² then
(x + 1)(x - 3) = 96 ( A = lw )
expand the factors on the left side
x² - 2x - 3 = 96 ( subtract 96 from both sides )
x² - 2x - 99 = 0 ← in standard form
(x - 11)(x + 9) = 0 ← in factored form
equate each factor to zero and solve for x
x - 11 = 0 ⇒ x = 11
x + 9 = 0 ⇒ x = - 9
but x > 0 ⇒ x = 11
length = 11 + 1 = 12 feet and width = 11 - 3 = 8 feet