Answer:
The area of the remaining board is (x² - 289) sq. ft.
Explanation:
Let the sides of the bigger square board be, x feet.
It is provided that a smaller square of side length 17 feet is cut out of the bigger square board.
The area of a square is:

Compute the area of the bigger square board as follows:

Compute the area of the smaller square board as follows:

Compute the area of the remaining board in square feet as follows:

![=[x^(2)-289]\ \text{square ft.}](https://img.qammunity.org/2021/formulas/mathematics/college/g18vd3ag9z0x1jgbo8uuye3itmmbo48nei.png)
Thus, the area of the remaining board is (x² - 289) sq. ft.