The perimeter of the parallelogram is 128 cm Its one side is 3 times longer than the other. Find the lengths of the sides.

In order to find the lengths of the sides of a parallelogram, we will compose and solve a linear equation using the formula for finding the perimeter of a parallelogram.

The condition says that the perimeter of the parallelogram is 128 cm. It is also known that one side is 3 times longer than the other.

Let us denote by the variable x cm the length of one of the sides, then the length of the second side can be written as 3x cm.

P = 2 (a + b);

2 (x + 3x) = 128;

x + 3x = 128: 2;

4x = 64;

x = 64: 4;

x = 16 cm length of one side, then 16 * 3 = 48 cm length of the second side.