Answer:
56
Step-by-step explanation:
Since vertical angles are equal, we know the two angles labeled are equal.
We can then set up an equation to get
[tex]19x-28=9x+52.[/tex]
Subtracting [tex]9x[/tex] from both sides to isolate the variable gives us
[tex]10x-28=52[/tex].
Then, adding [tex]28[/tex] to both sides gives
[tex]10x=80,[/tex]
and dividing both sides by 10 gives
[tex]x=8.[/tex]
Now, we can find the measure of [tex]9x+52[/tex] by plugging what we found for [tex]x[/tex] in:
[tex]9(x)+52=9(8)+52=72+52=124.[/tex]
Since the angles ? and 9x+52 make up a line, they are supplementary. Therefore, we have
[tex]?=180-(9x+52)=180-124=\boxed{56}.[/tex]