The width of the rectangle is 2 cm. What is its length if the perimeter is 8 cm?

The perimeter of a rectangle is the sum of the lengths of all its sides and is calculated by the formula:

P = 2 * a + 2 * b, or P = 2 * (a + b);

where a is the width, b is the length.

In our task, the width and perimeter are indicated, in order to find the length, we substitute these data into the formula and solve the resulting equation:

8 = 2 * (2 + b);

2 + b = 8: 2;

2 + b = 4;

b = 4 – 2;

b = 2 (cm).

Let’s check if we decided correctly and substitute the found length into the formula:

P = 2 * (2 + 2) = 2 * 4 = 8.

Answer: the length of the rectangle is 2 cm.