Which of the sets of ordered pairs represents a function? a = {(−4, 5), (1, −1), (2, −2), (2, 3)} b = {(2, 2), (3, −2), (9, 3), (9, −3)} only a only b both a and b neither a nor b

Given: lines a and b are parallel and line c is a transversal. prove: 2 is supplementary to 8 what is the missing reason in the proof? statement reason 1. a || b, is a transv 1. given 2. ∠6 ≅ ∠2 2. ? 3. m∠6 = m∠2 3. def. of congruent 4. ∠6 is supp. to ∠8 4. def. of linear pair 5. ∠2 is supp. to ∠8 5. congruent supplements theorem corresponding angles theorem alternate interior angles theorem vertical angles theorem alternate exterior angles theorem