# The perimeter of an isosceles triangle is 28 cm, and one of its sides is three times longer than the other.

**The perimeter of an isosceles triangle is 28 cm, and one of its sides is three times longer than the other. Calculate the sides of the triangle.**

Option number 1.

Let the side of this triangle be equal to the variable a.

Then the length of the base can be expressed as 3a.

Since we know that the perimeter is 28 cm, then we write down the equation and find out the lengths of the sides:

a + a + 3a = 28;

5a = 28;

a = 5.6;

3 * 5.6 = 16.8.

Answer: Lateral 5.6 cm, base 16.8.

Option number 2.

Let the base of this triangle be equal to the variable a.

Then the length of the lateral side can be expressed as 3a.

Since we know that the perimeter is 28 cm, then we write down the equation and find out the lengths of the sides:

3a + 3a + a = 28;

7a = 28;

a = 4;

3 * 4 = 12.

Answer: Side 12 cm, base – 4.