Question

Two sides of a triangle have lengths 15 and 20 units. What is the least number of units the third side could be?

A) 5 units.
B) 10 units.
C) 35 units.
D) 45 units.

Answer 1

The least number of units the third side of the triangle could be is 5 units.

Step-by-step explanation:

In a triangle, the sum of the lengths of any two sides must be greater than the length of the third side. This is known as the Triangle Inequality Theorem.

In this case, the two sides of the triangle have lengths 15 and 20 units. In order to find the least possible length for the third side, we subtract the two given side lengths from each other:

20 - 15 = 5 units

Therefore, the least number of units the third side could be is 5 units (option A).