Choose the coordinates of the vertices of the reflection. reflect parallelogram (1,0) (1,3) (4,1) (4,4) over the y-axis.

All of the coordinates are in the second quadrant which is + + which the x is positive and the y is positive. when you reflect the shape across the y-axis you move into quadrant 1 which is -+ so the points are now
(-1,0),(-1,3),(-4,1),(-4,4).
Hope this helps!

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