Question

in 8th-grade math, a ______ is an imaginary line that acts like a mirror, flipping a geometric figure to a new position called its image, which is a congruent, mirror image of the original. the flip can be across the y-axis or x-axis.

Explanation:

In 8th - grade math, the term that fits the description of "an imaginary line that acts like a mirror, flipping a geometric figure to a new position (its image, a congruent mirror image) and the flip can be across the y - axis or x - axis" is "line of reflection". The blank in the sentence should be filled with "line of reflection" as it is the concept in geometry related to reflections (flips) of geometric figures over a line (the line of reflection) which can be the x - axis, y - axis, or other lines.

Answer:

line of reflection