Given that $M( 1, -6)$ is the midpoint of $\overline{AB}$ and $A(-2, 1)$ is one endpoint, what is the sum of the coordinates of

Given that $M( 1, -6)$ is the midpoint of $\overline{AB}$ and $A(-2, 1)$ is one endpoint, what is the sum of the coordinates of point B?

 

I tried to do the latex on this one so it would be easier to read!