In an isosceles triangle, the perimeter is 15 cm. The base is 3 cm larger than the lateral side. Find the sides of the triangle.

Since the triangle ABC is isosceles, then AB = BC.
Let the length of the side of the triangle be X cm, AB = BC = X cm.
Then, according to the condition, the length of the base of the triangle will be equal to: AC = (X + 3) cm.
The perimeter of the triangle ABC will be equal to: Ravs = AB + BC + AC = X + X + X + 3 = 15 cm.
3 * X = 12 cm.
X = AB = BC = 12/3 = 4 cm.
AC = 4 + 3 = 7 cm.
Answer: The sides of the triangle are 4 cm, 4 cm, 7 cm.