The perimeter of a triangle is 7 cm, and one of the sides of this triangle is 2 times smaller

The perimeter of a triangle is 7 cm, and one of the sides of this triangle is 2 times smaller than the other side, twice the third, find the lengths of the sides of this triangle.

Let the third side of the triangle be x millimeters, then the first side is 3 * x millimeters, and the second side is 2 * 3 * x millimeters. We know that the perimeter of this triangle is 70 millimeters. Let’s make the equation:

x + 3 * x + 2 * 3 * x = 70;

x + 3 * x + 6 * x = 70;

x * (1 + 3 + 6) = 70;

x * 10 = 70 (in order to find an unknown factor, you need to divide the product by a known factor);

x = 70: 10;

x = 7 millimeters – the length of the third side of the triangle;

7 * 3 = 21 millimeters – the length of the first side of the triangle;

7 * 6 = 42 millimeters – the length of the second side of the triangle.

Answer: 7 millimeters; 21 mm; 42 mm.