Find the focal length (distance from vertex to focus) of the parabola y^2 = 12x.
Answer and explanation
Correct answer: C. 3
- Step 1: The standard form of a horizontal parabola with vertex at the origin is y^2 = 4px.
- Step 2: Equating coefficients gives 4p = 12, which implies p = 3. The focal length is p = 3.
Answer
3.
Why not the others: '6' divides 12 by 2 instead of 4; '12' assumes the coefficient is the focal distance directly; '1.5' divides 12 by 8.
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