To perform a dilation with a scale factor of 1/2 centered at the origin, we need to multiply the coordinates of each point by 1/2.
For point A (-6, 4), we multiply each coordinate by 1/2:
A' = (-6 * 1/2, 4 * 1/2)
A' = (-3, 2)
Similarly, for point B (-8, 2), we multiply each coordinate by 1/2:
B' = (-8 * 1/2, 2 * 1/2)
B' = (-4, 1)
Therefore, the coordinates of point A after the dilation are (-3, 2), and the coordinates of point B after the dilation are (-4, 1).