if point P (2,-8) is reflected across the line y=-2, what are the coordinates of its reflection image
To reflect a point across a line, we can use the following formula:
(x', y') = (x, -y + 2b)
where (x, y) is the original point and b is the y-intercept of the line across which the reflection is being performed.
In this case, the y-intercept of the line y = -2 is -2. So for the point P(2, -8), the reflected image will be:
(2, -(-8) + 2(-2))
(2, 8 + (-4))
(2, 4)
Therefore, the coordinates of the reflection image of point P across the line y = -2 is (2, 4).