Theorem equid1ALT 2255

Description: Alternate proof of equid 1791 and equid1 2237 from older axioms ax-c7 2216, ax-c10 2217 and ax-c9 2221. (Contributed by NM, 10-Jan-1993.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
equid1ALT

Proof of Theorem equid1ALT

Step	Hyp	Ref	Expression
1		ax-c9 2221	. . . . 5
2	1	pm2.43i 47	. . . 4
3	2	alimi 1633	. . 3
4		ax-c10 2217	. . 3
5	3, 4	syl 16	. 2
6		ax-c7 2216	. 2
7	5, 6	pm2.61i 164	1

Syntax hints:  -.wn 3  ->wi 4  A.wal 1393

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1618  ax-4 1631  ax-c7 2216  ax-c10 2217  ax-c9 2221