The perimeter of an isosceles triangle ABC is 30 cm, and one of the sides is 3 cm

The perimeter of an isosceles triangle ABC is 30 cm, and one of the sides is 3 cm larger than the other. What can be the sides of a triangle ABC?

The solution of the problem:
1. Let’s denote the length of the base of the triangle through x centimeters.
2. The second and third sides of the triangle are equal to (x + 3) centimeters.
3. Let’s compose and solve the equation.
x + (x + 3) + (x + 3) = 30;
x + x + 3 + x + 3 = 30;
x + x + x = 30 – 3 – 3;
3x = 24;
x = 24/3;
x = 8;
4. The length of the base of the triangle is x = 8 centimeters.
5. Let us calculate what is the length of the lateral side of an isosceles triangle.
x + 3 = 8 + 3 = 11 centimeters.
Answer: One side of an isosceles triangle is 8 cm. The second is 11 cm. The third is 11 cm.