SOLUTION: Identify the focus and directrix of the parabola y=-15x^2, 6x^2-3y=0, 2y^2+10x=0!?

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Question 914520: Identify the focus and directrix of the parabola y=-15x^2, 6x^2-3y=0, 2y^2+10x=0!?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
y = -15x^2 , Parabola opening up(a>0) or down(a<0), y=a%28x-h%29%5E2+%2Bk
C(0,0)
4p = 1%2Fa (Note: |4p| being the length of the latus rectum)
p = 1%2F4a = -1/60, F(0, -1/60), Directrix y = 1/60

........
y = 2x^2 , Parabola opening up(a>0) or down(a<0), y=a%28x-h%29%5E2+%2Bk
C(0,0)
p = 1%2F4a p = 1/8, F(0, 1/8), Directrix y = -1/8

............
x = -.2x^2 Parabola opening right(a>0) or left(a<0), x=a%28y-k%29%5E2+%2Bh
C(0,0)
p = 1%2F4a = -1/.8 = -1.25 F(-1.25 , 0), Directrix x = 1.25