The perimeter of an isosceles triangle is 64 cm. The side of this triangle is 20 mm less than the base

The perimeter of an isosceles triangle is 64 cm. The side of this triangle is 20 mm less than the base. Find the sum of the sides of this triangle.

From the condition it is known that the perimeter of an isosceles triangle is 64 cm. It is also known that the side of the triangle is less than the base by 20 mm = 2 cm. In order to find the sum of the sides of the triangle, we will apply the formula to find the perimeter of an isosceles triangle.

P = 2a + b, where a is the side of an isosceles triangle, b is the base.

Let’s denote by x cm the base of the triangle, then the side is (x – 2) cm.

We get the equation:

2 (x – 2) + x = 64;

2x – 4 + x = 60;

3x = 64;

x = 21 1/3 cm base length.

21 1/3 – 2 = 19 1/3 cm side.

2 * 58/3 = 116/3 = 38 2/3 cm.