Question

a rectangular porch has dimentions of (x+12) and (x+5) feet. If thr aria of the porch floor is 120 square feet, what is its length and width?

Answer 1

We have (x+12)·(x+5) = 120; where x > 0;
Then, x^2 + 17x + 60 = 120;
x^2 + 17x - 60 = 0;
The solutions are x1 = +3 and x2 = -20;
Then, x = 3 is the correct solution.
Finally, x + 12 = 15 feet (length) and x + 5 = 8 feet (width).