Parabolas (Sec 9-4) — Unit test

Question 1

Which graph represents the equation y2 = –4x?

Revolt · Accepted Answer

On a coordinate plane, a parabola opens to the left. It has a vertex at (0, 0), a focus at (negative 1, 0), and a directrix at x = 1.

Question 2

A parabola has a vertex at (0,0). The focus of the parabola is located on the positive x-axis.

Revolt · Accepted Answer

the negative part of the x-axis

Question 3

A parabola can be represented by the equation x2 = –20y.

Revolt · Accepted Answer

(0,–5)

Question 4

A parabola has a vertex at (0,0). The focus of the parabola is located on the positive y-axis.

Revolt · Accepted Answer

up

Question 5

On a coordinate plane, a parabola opens upward. It has a vertex at (0, 0), a focus at (0, 1.5) and a directrix at y = negative 1.5.

Revolt · Accepted Answer

x2 = 6y

Question 6

A parabola has a vertex at the origin. The equation of the directrix of the parabola is y = 3.

Revolt · Accepted Answer

(0,–3)

Question 7

A parabola has a vertex at (0,0). The focus of the parabola is located at (4,0).What is the equation of the directrix?

Revolt · Accepted Answer

x=−4

Question 8

A parabola has a vertex at (0,0). The equation for the directrix of the parabola is x = –4.

Revolt · Accepted Answer

right

Parabolas (Sec 9-4) — Unit test Answers