Answer:
There is only 1 Pythagorean triple b
a,c,d are not triples, they are not even a triangle
Step-by-step explanation:
There are 4 common Pythagorean triples. They can all be proven using the Pythagorean theorem
a^2 +b^2 = c^2 where a and b are the legs and c is the hypotenuse
(3, 4, 5), (5, 12, 13), (8, 15, 17) and (7, 24, 25) are the 5 common triples that should be memorized.
Lets check
a 2,3,6
2^2 +3^2 = 6^
4+9=36 this is not even a triangle
2+3 <6
The sum of 2 sides must be greater than the third
b)3,4,5
3^2 +4^2 = 5^2
9+16 =25
25=25 it is a triple
c)4,5,9
4^2 +5^2 = 9^2
16+25 = 81
39 = 81 This is not even a triangle
4+5 =9
The sum of 2 sides must be greater than the third
d)5,7,12
5^5 +7^2 = 12^2
25 +49 = 144
74 =144 this is not even a triangle
5+7=12
The sum of 2 sides must be greater than the third
