Theorem 9p1e10OLD 11361

Description: 9 + 1 = 10. (Contributed by Mario Carneiro, 18-Apr-2015.) Obsolete version of 9p1e10 11698 as of 8-Sep-2021. (New usage is discouraged.) (Proof modification is discouraged.)

Assertion

Ref	Expression
9p1e10OLD	⊢ (9 + 1) = 10

Proof of Theorem 9p1e10OLD

Step	Hyp	Ref	Expression
1		df-10OLD 11289	. 2 ⊢ 10 = (9 + 1)
2	1	eqcomi 2780	1 ⊢ (9 + 1) = 10

Syntax hints:   = wceq 1631  (class class class)co 6793  1c1 10139   + caddc 10141  9c9 11279  10c10 11280

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1870  ax-4 1885  ax-5 1991  ax-6 2057  ax-7 2093  ax-9 2154  ax-ext 2751

This theorem depends on definitions:  df-bi 197  df-an 383  df-ex 1853  df-cleq 2764  df-10OLD 11289

This theorem is referenced by:  dfdecOLD  11697  declecOLD  11746