Question

Which of these four sets of side lengths will form a right triangle?

Set 1
square root of 2 cm, 9 cm, square root of 7 cm.

Set 2
2 in, square root of 5 in, 9 in.

Set 3
square root of 6 mm, 2 mm, 10 mm

Set 4
square root of 2 ft, square root of 7 ft, 3ft

Answer 1

They must conform with Pythagoras theorem

It is set 4 because

(sqrt 2)^2 + (sqrt 7)^2 = 3^2
2 + 7 = 9