The figure below shows parallel lines cut by a transversal: which statement is true about ∠7 and ∠8? 1. ∠7 and ∠8 are supplementary because they are a pair of corresponding angles. 2. ∠7 and ∠8 are complementary because they are a pair of adjacent angles on a straight line. 3. ∠7 and ∠8 are congruent because they are a pair of adjacent angles on a straight line. 4. ∠7 and ∠8 are supplementary because they are a pair of adjacent angles that form a straight line.