Hello! i've been really stuck on this problem, can someone me? solve for x: 2.5(10-x) +21 = 84 - 3.5(3x + 20) you!

Someone answer this asap for the length, in feet, of a rectangular rug is represented by the expression 5x² + 2x. the width, in feet, is represented by the expression 3x². which expression represents the perimeter, in feet, of the rug? a. 8x² + 2x b. 8x² + 4x c. 16x² + 2x d. 16x² + 4x