Find the sides of a parallelogram if its perimeter is 36 cm and one side is twice as large as the other.

A parallelogram is a quadrangle in which opposite sides are pairwise parallel and equal.

Let us have a parallelogram of AВСD, then AB = CD and ВС =AD.

Let the sides AB = СD = x cm, then the sides BC = AD = 2 * x (cm) are twice as large.

Perimeter (the sum of the lengths of all sides) P = 2 * (a + b), where a and b are the sides of the parallelogram.

a = x, b = 2x.

By condition, it is known that the perimeter is 36 cm.

Let’s make an equation and find the value of x.

2 * (x + 2x) = 36;

(x + 2x) = 36: 2;

3x = 18;

x = 18: 3;

x = 6.

AB = CD = 6 cm.

BC = AD = 2 * 6 = 12 cm.

Answer: the sides of the parallelogram are 6 cm and 12 cm.