One side of the rectangle is 9 cm, and the other is 5 cm less. Find the area of the triangle.

In order to calculate the area of a rectangle, you need to find the product of its sides. From the problem statement, we know that the length of one of its sides is 9 cm. We need to find the length of the second side. We find it, if we also know that it is 5 cm shorter than the known side, we get:
9 – 5 = 4 cm.
And now, when we know both sides of the rectangle, let’s calculate what its area is.
9 * 4 = 36 cm ^ 2.
Answer: The area of the given rectangle is 36 cm ^ 2.