Theorem pncan3i

Description: Subtraction and addition of equals. (Contributed by NM, 26-Nov-1994)

	Ref	Expression
Hypotheses	negidi.1	$$⊢A\in ℂ$$
	pncan3i.2	$$⊢B\in ℂ$$
Assertion	pncan3i	$$⊢A+B-A=B$$

Proof

Step	Hyp	Ref	Expression
1		negidi.1	$$⊢A\in ℂ$$
2		pncan3i.2	$$⊢B\in ℂ$$
3		pncan3	$$⊢\left(A\in ℂ\wedge B\in ℂ\right)\to A+B-A=B$$
4	1 2 3	mp2an	$$⊢A+B-A=B$$