A: Yes, the sum of two sides are greater than the third side.
B: Yes, the sum of two sides are greater than the third side. (Would be an equiilateral triangl.)
C: No, the sum of two sides are less than the third side.
In general, To determine if 3 side lengths are a triangle, use the triangle inequality theorem, which states that the sum of 2 sides of a triangle must be greater than the third side. Therefore, all you have to do is add together each combination of 2 sides to see if it's greater than the third side.
