document.write( "Question 442284: I need help in writing an equation for a parabola with vertex at (4,-1) and directrix y = 1. Thank you \n" ); document.write( "

Algebra.Com's Answer #305167 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi
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document.write( "parabola with vertex at (4,-1) and directrix y = 1.
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document.write( "Directrix parallel to the x-axis. Parabola opening upward or downward.
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document.write( "Note: standard form is , where  the focus is (h,k + p)
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document.write( "and the directrix is -p distance from the vertex
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document.write( "vertex at (4,-1) directrix y = 1 Parabola opens downward
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document.write( " (x-4)^2 = -8(y+1)  |directrix y = 1 therefore: p = -2  4p = -8 
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document.write( "or y = (-1/8)(x-4)^2 - 1
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document.write( "ewatrrr@aol.com
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document.write( "private/pay tutoring Inquiries only, please. 
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