Question

Which of the following cannot be the side lengths of a triangle?

10, 12, 18

9, 9, 10

3, 11, 15

10, 15, 20

Answer 1

3, 11, 15

Explanation:

The two shorter sides add up to 14, which is smaller than 15, therefore making the triangle impossible as the sum of the two smaller sides have to be larger than the longest side