proposition: Lemma compose_le x y z : 0 ≤ z -> y = x + z -> x ≤ y.
proof: Proof. intros E1 E2. rewrite E2. apply nonneg_plus_le_compat_r. trivial. Qed.
imports: HoTT.Classes.theory.apartness HoTT.Classes.interfaces.abstract_algebra HoTT.Classes.interfaces.orders HoTT.Classes.theory.rings HoTT.Classes.orders.orders HoTT.Classes.orders.maps