Apply geometric motion to reflect figures. Brianna reflects point P over a line of reflection, resulting in point P'. If points P and P' have the same y coordinate, what must be true?

Question

a. The line of reflection is the x-axis
b. The line of reflection is the y-axis
c. The line of reflection is horizontal
d. The line of reflection is vertical

Answer 1

If points P and P' have the same y-coordinate after reflecting over a line of reflection, this indicates that the line of reflection is horizontal.

When a point is reflected over a horizontal line, the y-coordinate of the point and its reflection will be the same, while the x-coordinate may change depending on the position of the original point relative to the line of reflection.

Therefore, the correct answer is:

c. The line of reflection is horizontal.