The perimeter of an isosceles triangle is 20 cm. The side of the triangle is twice the length

The perimeter of an isosceles triangle is 20 cm. The side of the triangle is twice the length of its base, find the length of the base and side of the triangle

Given:

isosceles triangle ABC,

AB and BC – lateral sides,

AC is the base.

P ABC = 20 centimeters,

AB = 2 * AC.

Find the sides of the triangle ABC, that is, AB, BC, AC -?

Solution:

Consider an isosceles triangle ABC. His sides are equal, that is, AB = BC. Therefore, P ABC = AB + BC + AC;

R ABC = 2 * AC + 2 * AC + AC;

20 = AC * (1 + 2 + 1);

20 = AC * 5;

AC = 20: 5;

AC = 4 centimeters;

2 * 4 = 8 centimeters – the length of the AB base.

Answer: 4 centimeters; 8 centimeters; 8 centimeters.