Answer:
A. x-axis
Step-by-step explanation:
The answer is the x-axis because the trangle is an exact reflection flipped across the x-axis. We also know this was flipped across the x-axis because the x values do not change, but the y values are the exact opposite. For example, point M has coordinates (1,-1) while point M' has coordinates (1,1). This is the same for points K, K', J, and J'.
Hope this helps ;)
