tri<

Theorem.

Arguments:

a (obj), b (obj), c (obj),

Hypotheses:

(ceqb)
(aeqb)

Assertions:

(aeqc)

Proof:

Hyp Ref Line Expr
Hypo1(ceqb)
2(aeqb)
1ax-sym3(beqc)
2, 3tri4(aeqc)