Parabolas

The focus is always inside the parabola.

• true
• false

A parabola is the set of all points equidistant from the focus and the directrix.

• true
• false

All parabolas with a vertical directrix open the left or right.

• true
• false

(y-4)² = -8(x+1)
What direction does this parabola open?

• up
• down
• left
• right

(x+3)² = 4(y+5)
What is the equation of the directrix? (make a sketch)

• x = 4
• x = 2
• y = -4
• y = -6

If the directrix is y = 4 and the focus is at 
(3, 0), the value of p is (make a sketch):

• 8
• -8
• 2
• -2

Find the vertex, focus, and directrix of the parabola: x² = 28y (make a sketch)

• Vertex: (0, 0) Focus: (0,7) Directrix: y=-7
• Vertex: (0, 0) Focus: (7,0) Directrix: y=7
• Vertex: (0, 0) Focus: (0,-7) Directrix: x=-7
• Vertex: (0, 0) Focus: (7, 0) Directrix: x=7

The focus is at (2,0) and the vertex is at (-4,0).  What is the equation of the parabola? (make a sketch)

• y² = 24(x+4)
• (y+4)² = -12x
• x² = 16(y+4)
• (x+4)²  = -20y

(y-4)² = -8(x+1)
What are the coordinates for the focus? (make a sketch)

• (1,4)
• (-1,6)
• (-1,2)
• (-3,4)

What is the equation of this parabola?

• (y-1)² = -4(x-3)
• (y-1)²= 4(x+3)
• (y+1)² = 4(x-3)
• (y+1)² = -4(x+3)