Answer:
Step-by-step explanation:
Multiply out (6 + x)(9 + x) and set the result (product) = to 88 ft²:
54 + 9x + 6x + x² = 88 ft².
Then 54 + 15x + x² - 88 ft² = 0
Combining the constants, we get x² + 15x - 34 = 0
This factors easily to (x + 17)(x - 2) = 0, with the result that x = 2.
We conclude that if we increase both the 9 ft length and the 6 ft width by 2 ft, the new area will be 88 ft². Note that (9+2)(6+2) = 88.
We discard the x-value -17, as we are ADDING the quantity x to the original measurements (9 by 6 ft) to obtain new measurements (11 by 8 ft).