Answer:
[tex]55^{\circ}[/tex]
Step-by-step explanation:
By the Vertical Angle theorem, [tex]\angle 3 = 55^{\circ}[/tex].
By the parallel line theorem, [tex]\angle 7 = \angle 3 = 55^{\circ}.[/tex]
So, [tex]\boxed{\angle 7 = 55^{\circ}}[/tex] and we're done!.
