State if each set of three numbers can be the lengths of the sides of a triangle and explain why and how you got the answer.

13, 12, 26

No. It's no because if you do the correct math, you can see when you add the first side, 13 and 12, you get 25. 25 is < 26. All sides have to have a correct amount to be a triangle.

13+12>26

25>26 NO

12+26>13

38>13 YES

13+26>12

39>12 YES