Solving Systems Algebraically

Creating equivalent systems for solving by elimination is a helpful method when there is no additive inverse.

Which pair of numbers should be used to make an equivalent system containing y-terms that are additive inverses?

6x – 3y = 3
5x – 5y = 10

A. 5 and -3
B. -10 and 3
C. 5 and 6
D. 10 and 3

Can somebody explain this to me?