Question

Find the standard form of the equation of the parabola with a focus at (0, -9) and a directrix y = 9

Answer 1

Reorder the terms:
y = -9 + 2x

Solving
y = -9 + 2x

Solving for variable 'y'.

Move all terms containing y to the left, all other terms to the right.

Simplifying
y = -9 + 2x
-2x+y=-9
2x-y=9

Standard form is when all the variables are on the same side and there are no fractions, so in this case, we move the 2x

y=2x - 9
Subtract 2x from both sides

The final answer is -2x + y = -9