Which set could represent the side lengths of a triangle?

A

4 in., 6 in., 10 in.

B.

4 in., 5 in., 10 in.

С

5 in., 6 in., 12 in.

D

5 in., 5 in., 9 in.

The last one is correct

So, the sum of two sides have to be greater than the third side for it to create a triangle.

Option A:

4 + 6 = 10

The first 2 sides aren't greater than the third side so, this is incorrect.

Option B:

4 + 5 = 9

The first 2 sides aren't greater than the third side so, this incorrect.

Option C:

5 + 6 = 11

The first 2 sides aren't greater than the third side so, this incorrect.

Option D:

5 + 5 = 10

The first 2 sides are greater than the third side so, this correct.

Therefore, the answer is Option D.

Best of Luck!