The perimeter of the rectangle is 9 dm 2 cm. The length of one side is 3 dm 5 cm. Find the length of the second side.

In order to find the perimeter of the rectangle, you need to fold all its sides. Or add the length and width of the rectangle and multiply the result by 2: P = (a + b) * 2, where P is the perimeter of the rectangle, a is the length of the rectangle, and b is the width of the rectangle.

If the perimeter of the rectangle and one of its sides are known, then in order to find the other side of the rectangle, it is necessary to express from the formula:

a = P / 2 – b

But, first you need to convert the values ​​of the perimeter and known side:

9 dm 2 cm = 92 cm; 3 dm 5 cm = 35 cm.

a = 92/2 – 35 = 46 – 35 = 11 (cm) – the length of the second side of the rectangle.

Answer: 11 cm.