R, S,Q and P are the midpoints of OC, CB, BA and OA respectively. OR=a, CS=b and OP=c. show that RS is parallel to PQ mathswatch

An octagonal prism has jow many lateral faces?

1. ∠1 is complementary to ∠2 and ∠3 is complementary to ∠2. subtraction property of equality 2. m∠1 + m∠2 = 90 and m∠3 + m∠2 = 90 substitution 3. m∠1 + m∠2 = m∠3 + m∠2 definition of complementary 4. m∠1 = m∠3 given

Ineed to know how to write question one in mathematical terms