One of the sides of the square was reduced by 9 and the other was increased by 2 times, and a rectangle

One of the sides of the square was reduced by 9 and the other was increased by 2 times, and a rectangle with a perimeter of 72 cm was obtained. Find the length of the side of the square by the equation.

1. Take the side of the square as x cm.

2. Having reduced it by 9 cm, the side of the rectangle is equal to (x – 9) cm.

3. Having enlarged the side of the square by 2 times, we got the second side of the rectangle, equal to (x * 2) = 2x cm.

4. Let’s make an equation and find out what the side of the square is equal to if the perimeter of the resulting rectangle is 72 cm.

(x – 9) + (x – 9) + 2x + 2x = 72;

x – 9 + x – 9 + 2x + 2x = 72;

6x = 72 + 9 + 9;

6x = 90;

x = 90/6;

x = 15 cm.

Answer: The side of a given square is 15 cm.