# What lines, segments, or rays are parallel in the following figures and what postulate or theorem proves them parallel? In the first figure I found segment DA to be parallel to segment CB and DC to...

What lines, segments, or rays are parallel in the following figures and what postulate or theorem proves them parallel?

In the first figure I found segment DA to be parallel to segment CB and DC to be parallel to AB by the Consecutive Interior Angels Converse Theorem as they add up to 180 degrees so they are supplementary angles.

I'm quite confused about the next two figures. I'd really appreciate some advice to get me going.