The side of the rectangle is a = 4 cm, and the perimeter is 14 cm. What is the side b?

The perimeter of the rectangle P = 2 (a + b), the side a and the perimeter of P are known from the conditions of the problem. Let’s plug the numbers into the equation and solve it:

14 = 2 * (4 + b);

14 = 8 + 2b;

2b = 14 – 8;

2b = 6;

b = 3 (cm).

Let’s check the solution to the equation:

2 * (4 + 3) = 14;

14 = 14.

Answer: the side of rectangle b is 3 cm.