Question

Which is the equation of a parabola with vertex (0, 0), that opens to the left and

has a focal width of 12?
a. y2 = 12x
b. y2 = -12x
c.x = 12y
d. x = -12y

Answer 1

b. y^2 = -12x

Explanation:

The general form for the given parabola is y^2 = -4ax where the focus is at (-a, 0). The focal width is 4a which in this case = 12.

Answer 2

Explanation:

I'm going to guess that the square exponents are on the top y's only? then answer b) looks good