Its been ages since I have done any maths and im a little rusty. Can someone please show me how to do these?

(1) Find $\displaystyle 17^{-1} mod \ 130 $

(2) Hence solve the equation $\displaystyle 17x \equiv 123 (mod 130) $

and

Give the general solution tot he following system of equivalences

$\displaystyle x \equiv 3 (mod \ 5) $

$\displaystyle x \equiv 5 (mod \ 7) $

$\displaystyle x \equiv 8 (mod \ 12) $

Thanks to anyone who can help