SOLUTION: Find the equation of the parabola with vertex at (2, -1) and directrix y+2=0. Sketch the graph.

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Question 1170411: Find the equation of the parabola with vertex at (2, -1) and directrix y+2=0. Sketch the graph.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
That is directrix y=-2, and vertex (2,-1). These are 1 unit apart at their nearest points. Focus must be 1 unit above the vertex so focus is at (2,0). Do a quick sketch of these focus, vertex, and directrix. These indicate that vertex is a minimum.

You could form your equation based on %28x-h%29%5E2=4p%28y-k%29.

4p=4%2A1=4;

highlight%28%28x-2%29%5E2=4%28y%2B1%29%29