The point ( -6 , 8 ) is reflected across the y axis. what is the coordinates of the reflection

(6, 8)

Step-by-step explanation:

The y- axis (the vertical axis) acts as a mirror point.  When reflecting over the y axis, the y value will stay the same.  Think about looking into a mirror on your wall, your height is the same on both sides of the vertical reflecting object

The x-value will change and be the other side of the y-axis.  It will be the same distance away from the y-axis that is was, but will have an opposite sign.

Here is was 6 units to the left of the y-axis (where x values are negative), now it is 6 units to the right of the y-axis (where x values are positive)