In a triangle, two sides are 7 cm, and the third is 2 cm shorter. Find the perimeter of the triangle if possible.

This task is solved in two steps. First, we find the third side of the isosceles triangle, since it is said in the condition that it is 2 cm less, then the first step is to perform the subtraction. Next, we find the perimeter of the triangle. It is known that the sum of all sides is the perimeter. Decision:

1) 7-2 = 5 (cm) – the third side of the triangle;

2) 7 + 7 + 5 = 19 (cm) – the perimeter of the triangle.

Answer: The perimeter of the triangle is 19 cm.