The perimeter of the rectangle is 18 cm. The length is 3 cm more than the width. Find the lengths of the sides of the rectangle.

The perimeter of the rectangle corresponds to the formula:

P = 2a + 2b. According to the terms of the assignment, this value for such a figure is 18 cm, and the width is 3 cm less than the length. Let’s write the equation in which we take the smallest side as “x”:

2 * (x + 3) + 2x = 18.

Let’s expand the brackets:

2x + 6 + 2x = 18.

On the left side of the equation, we will perform actions with the coefficients of the variable, and transfer the known number to the right, while changing the sign in front of it to the opposite.

4x = 18 – 6 = 12.

The second factor is the quotient of the first.

x = 12: 4 = 3.

Therefore, width = 3 cm and length = 3 + 3 = 6 cm.