Theorem 9p5e14

Description: 9 + 5 = 14. (Contributed by Mario Carneiro, 19-Apr-2015)

	Ref	Expression
Assertion	9p5e14	⊢ ( 9 + 5 ) = ; 1 4

Proof

Step	Hyp	Ref	Expression
1		9nn0	⊢ 9 ∈ ℕ0
2		4nn0	⊢ 4 ∈ ℕ0
3		3nn0	⊢ 3 ∈ ℕ0
4		df-5	⊢ 5 = ( 4 + 1 )
5		df-4	⊢ 4 = ( 3 + 1 )
6		9p4e13	⊢ ( 9 + 4 ) = ; 1 3
7	1 2 3 4 5 6	6p5lem	⊢ ( 9 + 5 ) = ; 1 4