The area of a rectangle is 64 cm2 width is 4 cm, find the perimeter of the rectangle?

The area of the rectangle is calculated by the formula:
S = a * b.
According to the condition of the task, this value for such a figure is 64 cm², and the width = 4 cm. Let us express the length. The first factor is the quotient of the second:
a = S: b = 64: 4 = 16 cm.
The perimeter is the sum of all sides. Since the rectangle has opposite dimensions equal, it corresponds to the formula:
P = 2a + 2b = 2 * 16 + 2 * 4 = 32 + 8 = 40 cm.