The length of the L.R. Is 4 times the distance from the focus to the vertex. It's centered on the focus, and it's oriented perpendicular to the line connecting the focus and the vertex. Since the focus and vertex fall in line vertically in this case, that means the L.R. Is horizontal.
So what's the distance between (0,2) and (0,0)? The length of the L.R. Will be four times that length. So find two points who lie on a horizontal line, are centered at (0,2), and are spaced apart the appropriate length of the L.R.
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