The area of the rectangle is 64 cm, its length is 16 cm. Find the perimeter of the rectangle.

From the condition we know that the area of the rectangle is 64 cm2, and the length of one of the sides is 16 cm. In order to find the perimeter of the rectangle, we must find the lengths of the sides of the rectangle.
For this we will use the formula to find the area of a rectangle.
So, the area of a rectangle can be found by the formula:
S = a * b;
Substitute the known values and solve the linear equation:
16a = 64;
a = 64: 16;
a = 4 cm length of the second side of the rectangle.
To find the perimeter, use the formula:
P = 2 (a + b) = 2 (16 + 4) = 2 * 20 = 40 cm