18. Exemplar Example Problems I

1. Let $OA$, $OB$, $OC$ and $OD$ are rays in the anticlockwise direction such that $∠ AOB = ∠COD = 100^°$, $∠BOC = 82^°$ and $∠AOD = 78^°$. Is it true to say that $AOC$ and $BOD$ are lines?

 

2. A transversal intersects two lines in such a way that the two interior angles on the same side of the transversal are equal. Will the two lines always be parallel? Give reason for your answer.