Question

Which set of numbers could NOT represent the side lengths of a triangle.
1) 11, 11, 15
2) 18, 28, 40
3) 4, 8, 12
4) 3, 4, 5

Answer 1

an ideal triangle can only be formed if the 2 short sides sum up to longer than the longest side

Answer 2

so add you 2 smallest values and see if its bigger than the remaining larger value; if so, you got a triangle

Answer 3

and if not, then you dont :/