What is the standard equation of a parabola opening to the right with vertex at the origin?
A
y² = 4ax
B
x² = 4ay
C
y² = -4ax
D
x² = -4ay
Analysis & Theory
For a parabola opening to the right, the equation is y² = 4ax.
What is the standard equation of a parabola opening to the left with vertex at the origin?
A
y² = 4ax
B
y² = -4ax
C
x² = 4ay
D
x² = -4ay
Analysis & Theory
For a parabola opening to the left, the equation is y² = -4ax.
What is the standard equation of a parabola opening upwards with vertex at the origin?
A
x² = 4ay
B
x² = -4ay
C
y² = 4ax
D
y² = -4ax
Analysis & Theory
For a parabola opening upwards, the equation is x² = 4ay.
What is the standard equation of a parabola opening downwards with vertex at the origin?
A
x² = 4ay
B
x² = -4ay
C
y² = 4ax
D
y² = -4ax
Analysis & Theory
For a parabola opening downwards, the equation is x² = -4ay.
In the standard parabola y² = 4ax, what is the focus?
A
(a,0)
B
(-a,0)
C
(0,a)
D
(0,-a)
Analysis & Theory
For y² = 4ax, the focus lies at (a,0).
In the standard parabola x² = 4ay, what is the directrix?
A
x = -a
B
x = a
C
y = -a
D
y = a
Analysis & Theory
For x² = 4ay, the directrix is y = -a.