theorem eqmeq23d (G: wff) (a b c d n: nat): $ G -> a = b $ > $ G -> c = d $ > $ G -> (mod(n): a = c <-> mod(n): b = d) $;
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | eqidd | G -> n = n |
|
| 2 | hyp h1 | G -> a = b |
|
| 3 | hyp h2 | G -> c = d |
|
| 4 | 1, 2, 3 | eqmeqd | G -> (mod(n): a = c <-> mod(n): b = d) |