The sum of the two sides of a parallelogram is 15 cm. Their ratio is 3: 7 Find the length of the sides.

From the condition it is known that the sum of the two sides of the parallelogram is 15 cm, and it is also known that the sides are related as 3: 7.

We will solve the problem using the equation. To begin with, we introduce the coefficient of similarity k and then we write the lengths of the sides as 3k and 7k.

Knowing the sum of the sides, we can write the following equation:

3k + 7k = 15;

We solve the resulting equation:

k (3 + 7) = 15;

10k = 15;

k = 15:10;

k = 1.5 we found the coefficient of similarity and now it is quite easy to find the lengths of the sides of the rectangle:

The smaller one is 3 * 1.5 = 4.5 cm and the larger one is 7 * 1.5 = 10.5 cm.