Slader Let R be an equivalence relation on A, and suppose [a] and [b] are two equivalence classes of R. Show that if [a] and [b] are not disjoint, then [a] = [b].

Match the following reasons with the statements given to create the proof. 1. do = ob, ao = oc sas 2. doc = aob given 3. triangle cod congruent to triangle aob vertical angles are equal. 4. 1 = 2, ab = dc if two sides = and ||, then a parallelogram. 5. ab||dc if alternate interior angles =, then lines parallel. 6. abcd is a parallelogram cpcte