Theorem subid1i

Description: Identity law for subtraction. (Contributed by NM, 29-May-1999)

	Ref	Expression
Hypothesis	negidi.1	|- A e. CC
Assertion	subid1i	|- ( A - 0 ) = A

Proof

Step	Hyp	Ref	Expression
1		negidi.1	|- A e. CC
2		subid1	|- ( A e. CC -> ( A - 0 ) = A )
3	1 2	ax-mp	|- ( A - 0 ) = A