The perimeter of the rectangle is 48 cm, its width is 4 cm. Find the area of this rectangle.

The area of a rectangle is the product of its two adjacent sides.
We are given the perimeter of the rectangle. One of its sides is equal to 6. which means that the second side can be denoted as in.
Let’s make the equation:
4 + 4 + 2v = 48;
Let’s simplify this equation:
8 + 2v = 48;
Let’s transfer the known numbers to the other side:
2c = 40;
Find in by dividing both sides of the equation by this coefficient:
h = 20.
Area of the rectangle = 20 * 4 = 80.
Answer: the side is 20 cm, the area is 80 cm ^ 2.

Method 2.

Area = 4 * (48 – 4 * 2) / 2 = 80 cm ^ 2.