a line contains the points (6,-3) and (3,1). When this line is reflected across the y-axis, what are the two new points?
a (-6,-3) and (3,1)
b (-6,-3) and (-3,1)
c (-6,3) and (-3,-1)
d (6,3) and (3,-1)
To reflect a point across the y-axis, we change the sign of the x-coordinate while keeping the sign of the y-coordinate the same. So, when we reflect (6,-3) across the y-axis, we get (-6, -3). Similarly, when we reflect (3,1) across the y-axis, we get (-3, 1).
Therefore, the two new points are option b) (-6,-3) and (-3,1).