Metamath Proof Explorer


Theorem ineq2d

Description: Equality deduction for intersection of two classes. (Contributed by NM, 10-Apr-1994)

Ref Expression
Hypothesis ineq1d.1 φ A = B
Assertion ineq2d φ C A = C B

Proof

Step Hyp Ref Expression
1 ineq1d.1 φ A = B
2 ineq2 A = B C A = C B
3 1 2 syl φ C A = C B