The perimeter of the rectangle is 20 cm and one of the sides is 2 cm. How to find the second side.

It is known from the condition that the perimeter of the rectangle is 20 centimeters, and one of the sides is 2 centimeters.

To find the length of the second side of the rectangle, compose and solve a linear equation.

First of all, we recall the formula for finding the perimeter of a rectangle.

P = 2 (a + b).

Let us denote the unknown side with the help of the variable x centimeters and proceed to drawing up the equation.

2 (x + 2) = 20;

x + 2 = 20: 2;

x + 2 = 10;

We are looking for an unknown term:

x = 10 – 2;

x = 8 cm the length of the second side of the rectangle.