Question

Suppose that a rectangle has a perimeter of 17 meters. Express the area A(x) of the rectangle in terms of the length x of one of its sides.

I did what I know and got 8.5x+x^2 and it was wrong

Answer 1

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