theorem zeqmadd2d (G: wff) (a b c n: nat): $ G -> modZ(n): b = c $ > $ G -> modZ(n): a +Z b = a +Z c $;
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | zeqmadd2 | modZ(n): a +Z b = a +Z c <-> modZ(n): b = c |
|
| 2 | hyp h | G -> modZ(n): b = c |
|
| 3 | 1, 2 | sylibr | G -> modZ(n): a +Z b = a +Z c |