Question

Which set of side lengths is a Pythagorean triple?

1)1,3, 10
2)4,5,9
3)9, 40, 41
4)16, 30, 44

Answer 1

`\huge{\boxed{\text{3) \bf{9, 40, 41}}}}`

A Pythagorean triple is a set of three numbers where
`a^2 + b^2 = c^2`.

Trying 1:

`1^2+3^2=10^2`

`1+9=100`

`10=100`

Incorrect.

Trying 2:

`4^2+5^2=9^2`

`16+25=81`

`41=81`

Incorrect.

Trying 3:

`9^2+40^2=41^2`

`81+1600=1681`

`1681=1681`

Correct!

Trying 4: (unnecessary, but practice is good)

`16^2+30^2=44^2`

`256+900=1936`

`1156=1936`

Incorrect.