Question

Find an equation for the conic that satisfies the given conditions.

Parabola,   focus (- 4, 0),     directrix  x = 2

Answer 1

Step 1:

The focus of parabola and directrix .

Standard form of horizontal parabola .

Where center is , focus is and directrix is .

In this case

And .

Step 2:

Add the equations (1) and (2).

Substitute in equation (2).

.

Step 3:

Substitute the values , and in standard form.

Solution:

The parabola equation .