Explanation:
as this was a straight reflection from left to right, the line of reflection is a vertical line in the middle between both shapes.
we see that the x coordinate of e.g. A is -5, and of its reflected image H the x coordinate is +3.
the middle coordinate is A plus half of the distance.
the x distance HA = 3 - -5 = 3 + 5 = 8
so, the middle x coordinate is -5 + 8/2 = -5 + 4 = -1
therefore, the line of reflection is
x = -1
you have to draw a vertical (up/down) line through the point on the x-axis x = -1.
please consider that the rejected shapes look exactly like each other, because they are symmetric shapes.
a translation (shift) would seemingly look the same.
but a reflection is like in a mirror.
A is actually transformed into H.
B is actually transformed into G.
C is actually transformed into F.
D is actually transformed into E.