Final answer:
To reflect a triangle across the x-axis, change the sign of the y-coordinates while keeping the x-coordinates the same.
Step-by-step explanation:
The vertices of the triangle are P(-4, 1), Q(-2, -8), and R(8, -1). To reflect a point across the x-axis, we change the sign of the y-coordinate while keeping the x-coordinate the same. So, the x-coordinates of the image triangle will remain the same, but the y-coordinates will change sign. The vertices of the image triangle reflected across the x-axis are P(-4, -1), Q(-2, 8), and R(8, 1).
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