Answer:
3,4,5 is the Pythagorean triplet
Explanation:
A pythagorean triplet is when you have 3 consecutive numbers (for example 1,2,3 or 9,10,11). So since they've already given one of the numbers you can try doing trial and error to find out(use different combinations like 3,4,5 or 4,5,6) and see whether the Pythagoras theorem applies to it.