Write the equation of the parabola with a focus (-2,4) and directrix y = 0.

y=0 means sideways from the usual orientation. The definition of a parabola is equal distances of (x,y) to the focus and the directrix.  We equate squared distance:

(x + 2)² + (y - 4)² = (y - 0)²

x² + 4x + 4 + y² - 8y + 16 = y²

x² + 4x + 20 = 8y

We could divide by 8 to get y= something but let's just skip the fractions and answer

8y = x² + 4x + 20

lol

step-by-step explanation:

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.