Answer:
y² = 38x + 79
Explanation:
Since directrix is the line x = -13, then it means x + 13 = 0
Focus is F(-3, 9).
Let A(x, y) be any point inside the plane having the focus and directrix.
Let MA be the perpendicular distance from A to the directrix and it means that A lies on parabola provided FA = MA.
Thus;
√[(x - (-3))² + (y - 9)²] = (x + 13)
Squaring both sides gives;
(x + 3)² + (y - 9)² = (x + 13)²
>> (x² + 6x + 9) + (y² - 18x + 81) = x² + 26x + 169
>> 6x + 9 + y² - 18x + 81 = 26x + 169
>> y² = 26x + 12x + 169 - 90
>> y² = 38x + 79