How do you determine the coordinates of a point after a reflection in the you axis?

To determine the coordinates of a point after a reflection in the y-axis, you simply negate the x-coordinate while keeping the y-coordinate the same. For a point with coordinates ((x, y)), its reflection across the y-axis will be at ((-x, y)). This transformation effectively flips the point over the y-axis, maintaining its vertical position but reversing its horizontal position.