<span>Let the length of one side of the rectangle be x.
Then the opposite side of the rectangle also has a length of x.
The sum of the other two sides must be 17 - 2x.
So the length of one of these sides is 8.5 - x.
The length of two sides of the rectangle are x and 8.5 - x.
To find the area, we need to multiply these two values.
A(x) = (x) (8.5 - x) = 8.5x - x^2</span>
