Help me answer this problem!!

Question

The dimensions of a rectangle are x and y and its perimeter is 60 meters. Write the area A of the rectangle as a function of x.

Answer 1

The area as a function of x means an equation for the area that has only the variable x in it. Remember that the perimeter of the rectangle is equal to twice its width plus twice its heigh, or 2(x+y) = 60. Divide both sides by 2 to obtain x + y = 30. Solve for y. The area of a rectangle is A = x*y. Input the y equation you got from x + y = 30, and you will have an area A as a function of x.