[tex]\tt Step-by-step~explanation:[/tex]
[tex]\tt~1:[/tex]
First, let's observe the diagram. line a is parallel to line b, so that means ∠2 and ∠6 are congruent. They are corresponding angles.
[tex]\tt 2:[/tex]
If ∠2 and ∠6 measures 78º, then that means the angles that are vertical to these angles, ∠4 and ∠8, are also congruent to each other.
[tex]\large\boxed{\tt Our~final~answer:Angles~4,6,8}[/tex]
If you would like to know what the other angles' measures are, you could simply subtract 78º from 180. A straight line measures 180º.
[tex]\large\txt{\tt 180-78=102}[/tex]
[tex]\small\boxed{\tt Other~angles'~measures:~102}[/tex]
