The perimeter of the square is 20 cm, which is 6 cm less than the perimeter of the rectangle.

The perimeter of the square is 20 cm, which is 6 cm less than the perimeter of the rectangle. The side of the square is equal to the width of the rectangle, what is the length of the rectangle?

Let us express the side of the square, from the formula, to determine its perimeter:
P = 4a. The second factor is the quotient of the first:
a = P: 4.
According to the terms of the assignment, this value for such a figure is 20 cm, therefore:
a = 20: 4 = 5 cm.
The sum of all sides of the rectangle is 6 cm larger: P is rectangular. = 20 + 6 = 26 cm.
One of its sides = 5 cm, we find the length:
P = 2a + 2b, therefore: a = (P – 2b): 2 = (26 – 2 * 5): 2 = 16: 2 = 8 cm.