Question 1056968
Learn everything you need from these, if not well explained in your textbook:


<a href="https://www.youtube.com/watch?v=M8LGsQMwwj4">parabola equation from given focus and directrix, using Distance Formula and definition</a>


<a href="https://www.youtube.com/watch?v=Wworlx39KfQ">Same thing, different orientation, and vertex not at Origin</a>