Answer:
C. 12, 8, 5
Step-by-step explanation:Side lengths of any triangle must conform to the triangle inequality theorem, which says that the sum of the lengths of any of the two sides of the triangle is greater than the length of the third side.
This means:
a + b > c
a + c > b
b + c > a
Let's check each of the options to see which set are possible lengths for a triangle:
A. 6, 5, 11
6 + 11 > 5 ===> 17 > 5
5 + 11 > 6 ===> 16 > 6
6 + 5 > 11 ===> 11 > 11 (INCORRECT. Does not confirm to tye theorem)
Therefore, this set cannot be possible side lengths for a triangle.
B. 8, 1, 2
8 + 1 > 2 ===> 9 > 2
1 + 2 > 8 ===> 3 > 8 (INCORRECT)
8 + 2 > 1 ===> 10 > 1
This set cannot be possible side lengths for a triangle.
C. 12, 8, 5
12 + 8 > 5 ===> 20 > 5
8 + 5 > 12 ===> 13 > 12
12 + 5 > 8 ===> 17 > 8
All are correct, therefore these are possible side lengths for a triangle.