Theorem 6p4e10

Description: 6 + 4 = 10. (Contributed by NM, 5-Feb-2007) (Revised by Stanislas Polu, 7-Apr-2020) (Revised by AV, 6-Sep-2021)

	Ref	Expression
Assertion	6p4e10	$$⊢6+4=10$$

Proof

Step	Hyp	Ref	Expression
1		df-4	$$⊢4=3+1$$
2	1	oveq2i	$$⊢6+4=6+3+1$$
3		6cn	$$⊢6\in ℂ$$
4		3cn	$$⊢3\in ℂ$$
5		ax-1cn	$$⊢1\in ℂ$$
6	3 4 5	addassi	$$⊢6+3+1=6+3+1$$
7	2 6	eqtr4i	$$⊢6+4=6+3+1$$
8		6p3e9	$$⊢6+3=9$$
9	8	oveq1i	$$⊢6+3+1=9+1$$
10		9p1e10	$$⊢9+1=10$$
11	7 9 10	3eqtri	$$⊢6+4=10$$