Answer:
So, the sum of the 3 angles in a triangle is 180. 
What you would do is: 
180= 73+6x-4+7x+7. 
Then, you add the common coefficients: 
180=76+13x
Then you subtract: 
104=13x
Then you divide: 
x=8. 
Then substitute the x value into the A value to get 44, meaning that C is the correct answer.