The perimeter of the square is 2 times the perimeter of the rectangle.

The perimeter of the square is 2 times the perimeter of the rectangle. What is the length of the side of this square if the lengths of the sides of the rectangle are 4 cm and 2 cm?

1) Calculate the perimeter of the rectangle using the formula: P = (a + b) 2 = (4 + 2) 2 = 12 (cm);

2) Find the perimeter of the square: 12 2 = 24 (cm);

3) Find out what the size of the side of the square is equal to: a = P: 4 = 24: 4 = 6 (cm).

Answer: the length of the side of the square is 6 cm.