parabolas

What is the vertex of the parabola?

• (-3, -1)
• (3, 1)
• (1, 3)
• (-1, -3)

What is the center and radius of the circle whose equation is (x - 8)² + (y + 3)² = 4

• Center (-8, 3), Radius = 2
• Center (-8, 3), Radius = 4
• Center (8, -3), Radius = 2
• Center (8, -3), Radius = 4

Tags

CCSS.HSG.GPE.A.1

A parabola is the set of all points equidistant (the same distance) from the focus and the directrix.

Look at your notes!

• True

• False

• Maybe

• It depends on the weather

True or False?

When the x-part is squared and there is a negative coefficient, the parabola opens right.

• True

• False

Find the vertex, focus, and directrix of the parabola: x² = 28y

(SKETCH A GRAPH TO SEE IT)

• 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

Find the vertex, focus, and directrix of the parabola:

(1/40)x² = y

*Start by multiplying by 40 to get rid of the fraction!*

• Vertex: (0, 0) Focus: (-20,0) Directrix: x = 10

• Vertex: (0, 0) Focus: (0, 10) Directrix: y=10

• Vertex: (0, 0) Focus: (0,10) Directrix: y=-10

• Vertex: (0, 0) Focus: (0, -10) Directrix: y = 10

The focus is always inside the parabola.

• True

• False

What direction does the parabola point?

8x = (y - 2)²

• Up

• Down

• Left

• Right

What direction does this parabola open?

x² = 16y

• Up

• Down

• Left

• Right

What is the vertex of this parabola?

(x - 2)² = 16(y + 2)

• (2, 2)

• (2, -2)

• (16, 4)

• (-2, 2)