The perimeter of a parallelogram is 42 cm, and one side is 5 cm longer than the other.

| May 5, 2021 | education

The perimeter of a parallelogram is 42 cm, and one side is 5 cm longer than the other. Find the sides of a parallelogram.

Let one of the sides of the parallelogram be x cm, then the second will be (x + 5) cm, since, according to the condition of the problem, the second side is 5 cm longer than the first. The perimeter of this parallelogram is 42 cm, and the perimeter of the parallelogram is the sum of all sides, but since the parallel sides are equal, the perimeter of the parallelogram can be represented as the doubled sum of the two sides, and as a result we get the equation:

2 * (x + (x + 5)) = 42;

(2x + 5) = 42/2;

2x + 5 = 21;

2x = 21 – 5;

2x = 16;

x = 16/2;

x = 8 (cm) is the smaller side of the parallelogram.

8 + 5 = 13 cm – large side of the parallelogram.

Answer: the sides of the parallelogram are 8 cm and 13 cm.



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