Theorem 9ne0

Description: The number 9 is nonzero. (Contributed by SN, 22-Oct-2025)

	Ref	Expression
Assertion	9ne0	|- 9 =/= 0

Proof

Step	Hyp	Ref	Expression
1		9nn	|- 9 e. NN
2	1	nnne0i	|- 9 =/= 0