The area of the rectangle is 270 cm2, its length is 9 dm. Find the perimeter of this rectangle.

S = 270 cm².

a = 9 dm = 90 cm. Based on the fact that 1 dm = 10 cm.

b =?.

P =?.

The formula for determining the area of a rectangle is:
S = a * b, express the width from it:

b = S: a = 270: 90 = 3 cm.

The sum of all sides of such a figure is calculated by the formula:
P = 2a + 2b. Substitute the measurements and write the expression:

P = 2 * 90 + 2 * 3 = 180 + 6 = 186 cm – makes up the perimeter of the rectangle.