Answer:
12, 13, 4
Sum of the squares of the smaller 2 sides < longest side squared - OBTUSE SCALENE TRIANGLE
6, 4, 11
LONGEST SIDE GREATER THAN OR EQUAL TO THE SUM OF THE OTHER TWO SIDES - NO TRIANGLE.
7, 6, 5
Sum of the squares of the smaller 2 sides > longest side squared - ACUTE SCALENE TRIANGLE
3, 14.5, 17
Sum of the squares of the smaller 2 sides < longest side squared - OBTUSE SCALENE TRIANGLE
Explanation: