Question

Find the length of the hypotenuse of a right triangle with legs of 9 cm and 12 cm.
A.8cm

B.21cm

C.15 cm

D.225cm

Answer 1

i think its 21

Answer 2

9^2+12^2= 255
sqrt 255

= C. 15

Answer 3

15^2 = 225, not 255
but 15 is correct.
Remember your basic 3-4-5 right triangle?
scale it up by a factor of 3 and you get 9-12-15