Theorem 5m1e4

Description: 5 - 1 = 4. (Contributed by AV, 6-Sep-2021)

	Ref	Expression
Assertion	5m1e4	|- ( 5 - 1 ) = 4

Proof

Step	Hyp	Ref	Expression
1		4cn	|- 4 e. CC
2		ax-1cn	|- 1 e. CC
3		df-5	|- 5 = ( 4 + 1 )
4	1 2 3	mvrraddi	|- ( 5 - 1 ) = 4