Quiz question please help

Question

If two rays are opposite rays, then their union is a straight line. True or false

Answer 1

True, by definition!

Answer 2

Depending on how you view it, probably.

It sounds about right.

but rays are already lines. If they're opposite rays, they go in opposite directions. They're parallel, but if their endpoints are not the same, you'll just get two rays with a gap between them, or they may overlap. IF the endpoints of each ray is the same, then yes, their union is one straight line, going to infinity in both directions.

Depending on the usage, you may just presume their endpoints are the same.