Answer:
Q' = (6,3)
Explanation:
You can think of this problem in two ways:
Graph:
I've shown my working for this, where I've counted how many units it takes to get from point Q to the axis through which im reflecting. There are 6 units between Q and the y axis, so naturally there should be 6 units between Q' and the y axis.
Coordinates:
Since this is a reflection through an axis, we can assume that the the x coordinate of point Q' will be equal and opposite to Q. Therefore, while the x coordinate of Q was -6, of Q' it's 6