Question

Which is the focus of a parabola with equation mc003-1.jpg?
(–1, 0)
(0, –1)
(0, 1)
(1, 0)

Answer 1

I can’t see the image file you referenced. Could you either paste the equation here or re-upload the image?

Meanwhile, here are the standard-focus results so you can match them to your equation:

- x^2 = 4py has vertex (0,0) and focus (0,p). So p = 1 → (0,1); p = −1 → (0,−1).
- y^2 = 4px has vertex (0,0) and focus (p,0). So p = 1 → (1,0); p = −1 → (−1,0).

So:
- x^2 = 4y → focus (0,1)
- x^2 = −4y → focus (0,−1)
- y^2 = 4x → focus (1,0)
- y^2 = −4x → focus (−1,0)

Tell me which equation is in mc003-1.jpg and I’ll give the selected choice.