And explain how you got the answer! point m is the midpoint of ab. the coordinates of point a are (-6,1) and the coordinates of m are (-2,2). what are the coordinates of point b?

I got (2,3)
I found the gradient between point A and point M which is (change in X / change in Y)
Which gave me 4
So for every 4 you go across on the X axis you go up 1 on the Y axis.
I find it helpful to draw out a sketch of a graph and draw lines between each spaces.
That is how I would do it. I hope you understand and I hope I made sense.
My answer may be wrong but that is how I would work it out.