Answer:
width = 3 inches
length = 18 inches
Explanation:
let width of the rectangle = x
length = 9 + 3x
area of the rectangle = length * width
given the area of the rectangle = 54 inches²
by substituting the values in the formula,
54 = x * (9 + 3x)
54 = 9x + 3x²
3x² + 9x - 54 = 0
dividing the whole equation by (3)
x² + 3x - 18 = 0
x² + 6x - 3x - 18 = 0
x(x + 6) - 3(x + 6) = 0
(x - 3)(x + 6) = 0
x = 3 or x = -6
thus, width of the rectangle, x = 3 inches
as we are assuming the width of the rectangle so we will take the positive value of x and will ignore the negative value.
length of the rectangle = 9 + 3x = 9 + 3(3) = 9 + 9 = 18 inches