Question

HELP!

Answer 1

A)
8^2+9^2=c^264+81=c^2
c^2=145c=sqrt 145c=12.04
B)
Pythagerean Theorum: 
A^2+B^2=C^2, where C is the hypotenuse and A and B are the other legs 
15^2=9^2+B^2 
225=81+B^2 
225-81=B^2 
144=B^2 (square root both sides) 
12=B