Question

Maggie constructs a triangle with sides lengths 7 centimeters long and 10 centimeters long.

Which is not a possible length for the third side?
A)16 centimeters

B)4 centimeters

C)2 centimeters

D)7 centimeters

Answer 1

C) 2 Centimeters

Explanation:

The Triangle Inequality Theorem states that sum of any two sides of a triangle has to be greater than the measure of the 3rd side. So lets use the 2 centimeters option to explain this. Say now we have a triangle with side lengths that are 7 centimeters long, 10 centimeters long, and 2 centimeters long. 7+10=17, which is greater than two. However 7+2=9, which is not greater then 10. Therefore it is not following the Triangle Inequality Theorem. So the length 2 centimeters is not a possible length for the third side.