Theorem 5lt9

Description: 5 is less than 9. (Contributed by Mario Carneiro, 9-Mar-2015)

	Ref	Expression
Assertion	5lt9	$$⊢5<9$$

Proof

Step	Hyp	Ref	Expression
1		5lt6	$$⊢5<6$$
2		6lt9	$$⊢6<9$$
3		5re	$$⊢5\in ℝ$$
4		6re	$$⊢6\in ℝ$$
5		9re	$$⊢9\in ℝ$$
6	3 4 5	lttri	$$⊢\left(5<6\wedge 6<9\right)\to 5<9$$
7	1 2 6	mp2an	$$⊢5<9$$