Triangle ABC is shown below: Triangle ABC is shown. A is at 2, 1. B is at negative 1, 4. C is at 3, 7. If triangle ABC is reflected over the x-axis, which of the following shows the coordinates for point B'?

AnswerCoordinates of point B': B' = (-1, -4)ExplanationTo reflect a point or a figure across the x-axis we use the rule: [tex](x,y)[/tex]→[tex](x,-y)[/tex]In other words, we multiply the y-coordinate of our points by -1, while leaving the original x-coordinate as it is. Let's apply the rule to every point of our triangle :A = (2, 1)A' = (2, 1*-1) = (2, -1)B = (-1, 4) B' = (-1, 4*-1) = (-1, -4)C = (3, 7)C' = (3, 7*-1) = (3, -7)