Respuesta :

a*a + b*b = c*c
9*9 + 12*12 = c*c
81 + 144 = c*c
225 = c*c
✓225 = 15
c = 15
The hypotenuse is 15.

I am assuming you mean hypotenuse of a right triangle with sides 12 and 9

using the pythagorean theorem

a^2 +b^2 =c^2 where a and b are the sides and c is the hypotenuse

12^2 +9^2 = c^2

144 +81 = c^2

225 = c^2

c=15

The hypotenuse is 15 mi