Theorem 9t2e18

Description: 9 times 2 equals 18. (Contributed by Mario Carneiro, 19-Apr-2015)

	Ref	Expression
Assertion	9t2e18	⊢ ( 9 · 2 ) = ; 1 8

Proof

Step	Hyp	Ref	Expression
1		9cn	⊢ 9 ∈ ℂ
2	1	times2i	⊢ ( 9 · 2 ) = ( 9 + 9 )
3		9p9e18	⊢ ( 9 + 9 ) = ; 1 8
4	2 3	eqtri	⊢ ( 9 · 2 ) = ; 1 8