Answer:
yes, it is right triangle
Step-by-step explanation:
to know if it is right triangle or not, you need to assume that the longest side is the hypotenuse which is 13.
next, the angle between 12 and 5 must be 90 to prove that it was right triangle
to prove that, let's use cosinus theorem
[tex] {13}^{2} = {12}^{2} + {5}^{2} - 2(12)(5) \cos(x) \\ 2(12)(5) \cos(x) = {12}^{2} + {5}^{2} - {13}^{2} \\ \cos(x) = \frac{ {12}^{2} + {5}^{2} - {13}^{2} }{2(12)(5)} \\ \cos(x ) = 0 \\ x = 90[/tex]
from that, we know it is a right triangle