It is known that the perimeter of a rectangle is 45cm and the length of one side is ACM, then the area of the rectangle is as follows:

It is known that the perimeter of a rectangle is 45cm and the length of one side is ACM, then the area of the rectangle is as follows:

Because one side of the rectangle is ACM, the other side is (45-2a) / 2 cm
So, the area of rectangle = a (45-2a) / 2 = 45A / 2-A & # 178; (CM & # 178;)