Use the image to answer the question.

Triangle ABC
𝐴
𝐵
𝐶
has been reflected over a vertical line of reflection. The coordinates of vertices A
𝐴
, B
𝐵
, C
𝐶
, and B′
𝐵

are shown. What are the coordinates of vertex A′
𝐴

?

(1 point)
The coordinates of vertex A′
𝐴

are (,).

1 answer

To determine the coordinates of the reflected vertex A′, we need to know the coordinates of vertex A and the position of the vertical line of reflection.

Generally, when a point (x, y) is reflected over a vertical line (like x = k), the new point A′ will have the same y-coordinate but the x-coordinate will mirror over the line of reflection. The formula for reflecting a point (x, y) over a vertical line x = k is as follows:

  • A(x, y) becomes A′(2k - x, y)

If you provide the coordinates of vertex A and the vertical line of reflection, I can calculate the coordinates of A′ for you!