The rectangle is divided into squares. Find the perimeter of the rectangle if the side of the filled square is 9cm.

Knowing the width and length of the rectangle, you can find its perimeter: P = (a + b) * 2, where P is the perimeter, a is the length, and b is the width. The side of the square is 9 cm, and the rectangle is divided into squares, which means that the width of the rectangle is also 9 cm.A square has all sides equal, and the rectangle is divided into squares, and the side of the square is 9 cm, then the length of the rectangle is 9 * 2 = 18 cm. Because both the width and length of the rectangle are known, we will find its perimeter:

P = (9 + 18) * 2 = 27 * 2 = 54 cm.

Answer: 54 cm.