Answer:
d. 17.5 and 28 units
Explanation:
An area of a rectangle is length times width. 8x times 5x = 40x^2. 40x^2 is eqaul to 500. After dividing by 40 and taking the square root of the quotient, x is approximately 3.54. 5 times 3.54 and 8 times 3.54 will yield approximately 17.5 and 28 units.