3,9,10 >>> not a right triangle. because 3^2 + 9^2 is not equal to 10^2
27, 36, 45 >>> yes, a right triangle bc 27^2 + 36^2 = 45^2
11,13,17 >>>
11^2 + 13^2 = 290
The sqrt of 290 = 17.0293863659.
If you are in the lower grades, probably your teacher expects you to round this to 17. I honestly don't know how to answer bc I don't know what your teacher's expectations are for rounding.
I am a precise person, but I could see a teacher accepting YES RIGHT TRIANGLE bc it's basically 17.
4, 8, 9 >>> NOT a right triangle.
4^2 + 8^2 = 80
The sqrt of 80 = 8.94427191
I would say NO because this does not equal 9!