Find an equation of the parabola described.
-Focus at (-3, 0); directrix the line x = 3
A) $y ^ { 2 } = - 12 x$
B) $x ^ { 2 } = - 12 y$
C) $y ^ { 2 } = - 3 x$
D) $y ^ { 2 } = 12 x$

Question

Find an equation of the parabola described.
-Focus at (-3, 0); directrix the line x = 3 
A) $y ^ { 2 } = - 12 x$
B) $x ^ { 2 } = - 12 y$
C) $y ^ { 2 } = - 3 x$
D) $y ^ { 2 } = 12 x$

Quizplus · Accepted Answer

The correct equation is $y^2 = -12x$ because the focus is at (-3, 0) and the directrix is x = 3, indicating a horizontal parabola opening to the left. The distance from the focus to the directrix is 6, so $4p = -12$, where $p = -3$, matching the form $y^2 = 4px$.

Find an Equation of the Parabola Described y2=−12xy ^ { 2 } = - 12 xy2=−12x

Find an Equation of the Parabola Described $y ^ { 2 } = - 12 x$