Given: isosceles triangle ABC, AB = BC more by 6 cm AC. Find all sides if the perimeter is known. Perimeter = 60 cm.

Consider an isosceles triangle ABC.

Let its base AC be equal to x cm, according to the condition of the problem, its edges AB = BC are more than the base by 6 cm, i.e. they will be equal to (x + 6) cm.

Since the perimeter of this triangle is 60 cm, we will compose and write down the equation:

x + (x + 6) + (x + 6) = 60;

3x + 12 = 60;

3x = 60 – 12;

3x = 48;

x = 48/3;

x = 16.

We got that the base of the AC is 16 cm. Since the sides are 6 cm larger than the base, then AB = BC = 16 + 6 = 22 (cm).

Answer: AC = 16 cm, AB = BC = 22 cm.