The perimeter of the triangle is 25cm, one side is 9cm, the other is 12cm

The perimeter of the triangle is 25cm, one side is 9cm, the other is 12cm, and the third side is unknown. How many cm is the third side larger than the first?

In order to find by how many centimeters the third side is larger than the first, we will find the length of the third side, for this we recall and apply the formula for finding the perimeter of a triangle.

The condition says that the perimeter of the triangle is 25 cm.And it is also known that one side is 9 cm, and the other is 12 cm.

First of all, we will find the length of the third side. We denote it by x cm.

P = a + b + c is the perimeter of the triangle.

9 + 12 + x = 25;

x = 25 – 9 – 12;

x = 4 cm length of the third side.

9 – 4 = 5 cm the first side is larger than the third.