Answer: 12, 12, and 23
Step-by-step explanation:
By definition, when three lengths form a triangle, the sum of two of them must be greater that the third lenght.
To find out which of the options given in the problem form a triangle, you must add the first two lenghts and verify that the sum is greater than the third lenght.
Keeping this on mind, when you verify the last option you have:
12+12=24
24>23
Therefore, the answer is the last option.
