When a point (a,b) is reflected in the y-axis, its image is the point (- a,b).
Practice makes perfect
Let's begin by drawing △ ABC
Next, we will do the transformation
(x,y)→ (x-9,y)
which is a translation of 9 units to the left. Now we can draw △ A'B'C'.
To complete the glide reflection, we will have to reflect △ A'B'C' in y=1. To do that we need to map all of the vertices of △ A'B'C' to A'', B'' and C'' so that y=1 is the perpendicular bisector to A'A'', B'B'', and C'C''.
Let's remove the unnecessary parts of the glide reflection.
