# SOLUTION: I need help in writing an equation for a parabola with vertex at (4,-1) and directrix y = 1. Thank you

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 Click here to see ALL problems on Quadratic-relations-and-conic-sections Question 442284: I need help in writing an equation for a parabola with vertex at (4,-1) and directrix y = 1. Thank youAnswer by ewatrrr(10682)   (Show Source): You can put this solution on YOUR website! ``` Hi parabola with vertex at (4,-1) and directrix y = 1. Directrix parallel to the x-axis. Parabola opening upward or downward. Note: standard form is , where the focus is (h,k + p) and the directrix is -p distance from the vertex vertex at (4,-1) directrix y = 1 Parabola opens downward (x-4)^2 = -8(y+1) |directrix y = 1 therefore: p = -2 4p = -8 or y = (-1/8)(x-4)^2 - 1 ewatrrr@aol.com private/pay tutoring Inquiries only, please. ```