Answer: A) Reflection along the line y = -1
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Explanation:
Point A is at (1,5). Point A' is at (1,-7).
Apply the midpoint formula to find the center of these two points.
You should get (1,-1) as that midpoint.
Follow these steps for B(-1,3) and B'(-1,-5) to get the midpoint (-1,-1)
Those midpoints we found are located on the mirror line. We only need two such points to plot it. Drawing a line through (1,-1) and (-1,-1) graphs the equation y = -1. This is the horizontal line through -1 on the y axis.