Question:
Write the coordinates of the vertices after a reflection across the y-axis.
P (-7, -8) -> P' (___,___)
Q (-7, -1) -> Q' (___,___)
R (0, -1) -> R' (___,___)
Solution:
When you reflect a point across the y-axis, then the y-coordinate remains the same, but the x-coordinate is transformed into its opposite (its sign is changed). Then the correct answer is:
P (-7, -8) -> P' (7,-8)
Q (-7, -1) -> Q' (7,-1)
R (0, -1) -> R' (0,-1)