How do you find the equation of the parabola whose focus is at (3, 3) and whose directrix is at x = 7?
A quadratic relation (or function) can be in the form:
Since our diretrix is a vertical line, our parabola is horizontal.
We, therefore, use the form
In this form, the focus is at
Using our information, the focus is at
We add the second and the third equations to get:
Let's plug in what we know: