The perimeter of the rectangle is 14 cm, the width is 3 cm less than the length. Find the sides.

In order to find the sides of a rectangle, we will recall the properties of the sides of a rectangle and the formula for finding the perimeter of a rectangle.
So, from the condition it is known that the width of the rectangle is 3 cm less than the length, and its perimeter is 14 cm.
The opposite sides of the rectangle are equal to each other.
We denote by x cm the length of the rectangle, then the width of the rectangle can be written as (x – 3) cm.
P = 2 (a + b);
2 (x + (x – 3)) = 14;
x + x – 3 = 14: 2;
2x – 3 = 7;
2x = 7 + 3;
2x = 10;
x = 10: 2;
x = 5 cm length and 5 – 3 = 2 cm width of the rectangle.