Question

Derive the equation of the parabola with a focus at (−5, 5) and a directrix of y = -1.

Answer 1

http://www.purplemath.com/modules/parabola.htm

Answer 2

so have you plotted the information, as it will help to determine the concavity...

Answer 3

no i havent

Answer 4

well its always a help

the focus is above the directrix, so the parabola is concave up

Answer 5

ok... so here is a quick and dirty method...

you need to find the focal length...

Answer 6

so start by finding the perpendicular distance from the focus to the directrix...