Answer:
56
Explanation:
Since vertical angles are equal, we know the two angles labeled are equal.
We can then set up an equation to get

Subtracting 
 from both sides to isolate the variable gives us
.
Then, adding 
 to both sides gives 

and dividing both sides by 10 gives

Now, we can find the measure of 
 by plugging what we found for 
 in:

Since the angles ? and 9x+52 make up a line, they are supplementary. Therefore, we have 
