Metamath Proof Explorer


Theorem sylan9eqr

Description: An equality transitivity deduction. (Contributed by NM, 8-May-1994)

Ref Expression
Hypotheses sylan9eqr.1 φ A = B
sylan9eqr.2 ψ B = C
Assertion sylan9eqr ψ φ A = C

Proof

Step Hyp Ref Expression
1 sylan9eqr.1 φ A = B
2 sylan9eqr.2 ψ B = C
3 1 2 sylan9eq φ ψ A = C
4 3 ancoms ψ φ A = C