WOLFRAM|DEMONSTRATIONS PROJECT

General Parabola Equation

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2

(-0.31x-0.95y-0.12)

-

2

(0.74+x)

-

2

(-2.62+y)

Let the equation of the directrix of a parabola be the normalized line

Ax+By+C=0

, where the point

(A,B)

is on the unit circle. Let the focus be

(

f

1

,

f

2

)

. The equation of the parabola is then

2

(Ax+By+C)

=

2

(x-

f

1

)

+

2

(y-

f

2

)

.