I need help with these three short problems. Help is greatly appreciated!

Solve for the variable requested and simplify the answer. You don't need to understand what the equations mean to complete the problems.

1. m*x=m*y+m*y ; solve for y

2. sinX=a/b ; solve for x

3. 1/z= 1/x + 1/y ; solve for x

Thank you for any help!!