In a triangle ABC AB = BC = 25 cm, and the AC side is 4 cm smaller than AB. Find the perimeter of the triangle.

The perimeter of a triangle is the sum of all its sides. By the condition of the problem, we know that the two sides of the triangle are equal to each other and are 25 cm. The third side is 4 cm less than the side AB. This means that we must subtract 4 cm from the size of the AB side.

Find the side of the speaker:

25 cm – 4 cm = 21 cm.

Now all sides of the triangle are known and we can find the perimeter:

P = AC + AB + BC.

P = 21 + 25 +25 = 71 cm.

Answer: The perimeter of the triangle is 71 centimeters.