Theorem bj-xtageq

Description: The products of a given class and the tagging of either of two equal classes are equal. (Contributed by BJ, 6-Apr-2019)

	Ref	Expression
Assertion	bj-xtageq	$$⊢A=B\to C\times tagA=C\times tagB$$

Proof

Step	Hyp	Ref	Expression
1		bj-tageq	$$⊢A=B\to tagA=tagB$$
2	1	xpeq2d	$$⊢A=B\to C\times tagA=C\times tagB$$