Theorem breqtri 3816

Description: Substitution of equal classes into a binary relation. (Contributed by NM, 5-Aug-1993.)

Hypotheses

Ref	Expression
breqtr.1	⊢ 𝐴𝑅𝐵
breqtr.2	⊢ 𝐵 = 𝐶

Assertion

Ref	Expression
breqtri	⊢ 𝐴𝑅𝐶

Proof of Theorem breqtri

Step	Hyp	Ref	Expression
1		breqtr.1	. 2 ⊢ 𝐴𝑅𝐵
2		breqtr.2	. . 3 ⊢ 𝐵 = 𝐶
3	2	breq2i 3801	. 2 ⊢ (𝐴𝑅𝐵 ↔ 𝐴𝑅𝐶)
4	1, 3	mpbi 143	1 ⊢ 𝐴𝑅𝐶

Syntax hints:   = wceq 1285   class class class wbr 3793

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-io 663  ax-5 1377  ax-7 1378  ax-gen 1379  ax-ie1 1423  ax-ie2 1424  ax-8 1436  ax-10 1437  ax-11 1438  ax-i12 1439  ax-bndl 1440  ax-4 1441  ax-17 1460  ax-i9 1464  ax-ial 1468  ax-i5r 1469  ax-ext 2064

This theorem depends on definitions:  df-bi 115  df-3an 922  df-tru 1288  df-nf 1391  df-sb 1687  df-clab 2069  df-cleq 2075  df-clel 2078  df-nfc 2209  df-v 2604  df-un 2978  df-sn 3412  df-pr 3413  df-op 3415  df-br 3794

This theorem is referenced by:  breqtrri  3818  3brtr3i  3820  le9lt10  8584  9lt10  8688  sqrt2gt1lt2  10073  z4even  10460  ex-fl  10741