The perimeter of the rectangle is 26 cm. Its length is 3 cm longer than its width. Find the sides of the rectangle.

P = 26 cm, length a = x + 3, width b = x.

The sum of all sides (perimeter) is calculated by the formula:

P = 2a + 2b. Let’s make the equation:

2 * (x + 3) + 2 * x = 26. Let’s open the brackets:

2x + 6 + 2x = 26. Let’s perform actions with the coefficients of the variable on the left side of the equation, and transfer the number to the right, while the sign in front of it changes to the opposite:

4x = 26 – 6 = 20.

x = 20: 4 = 5.

It turns out that the width = 5 cm, and the length = 5 + 3 = 8 cm.