# Math Help - Question in Euclidean geometry(Please help)

Proved that

2. ## Re: Question in Euclidean geometry(Please help)

Originally Posted by soso123
Proved that
This is just a matter of applying definitions.

$\overrightarrow {AB} = \overline {AB} \cup \left\{ {X:A - B - X} \right\}$.

Now combine that with $\overrightarrow {BA}$ to get the set $\overleftrightarrow {AB}$.

3. ## Re: Question in Euclidean geometry(Please help)

Thank you very much