In a triangle, the first side is x cm larger than the second and 5 cm less than the third side.

In a triangle, the first side is x cm larger than the second and 5 cm less than the third side. The length of the second side is 10 cm. Write it as an expression: What is the perimeter of the triangle.

Find what is the length of the first side of this triangle.

From the condition of the problem it is known that the first side of this triangle is x cm larger than the second, and the length of the second side is 10 cm, therefore, the length of the first side of this triangle is x + 10 cm.

Find what is the length of the third side of this triangle.

According to the condition of the problem, the first side of this triangle is 5 cm less than its third side, therefore, the length of the third side of this triangle is x + 10 + 5 = x + 15 cm.

Then the perimeter of this triangle is x + 10 + 10 + x + 15 = 2x + 35 cm.

Answer: the perimeter of this triangle is 2x + 35 cm.

One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.