Question

Plot a point A(3,-6) in x axis as point B and then plot the reflection of B in y axis.

Answer 1

See the reflection or  image  A'  of the point A(3, -6)..

Draw a perpendicular from A on to the line (y-axis) . Then note the perpendicular distance .  Here it is 3 units. Now extend the perpendicular to the other side of   the line (y-axis).  Then find the point  3 units distance from y axis...  That is   (-3, -6).