Back to Quadratics

Understanding Parabolas

100

What part of ax²+c makes it open up or down?

If the a is positive or negative.

200

What is the c in ax²+c?

The y-intercept

300

Compare y=1/4 x²  with its parent.

There is a shrink.

400

Compare y=6 x²  with its parent.

There is a stretch.

500

Compare y= -1/3x² -4  with its parent.

reflection, shrink, translation down 4

Vocab

100

What is the name of the graph of a quadratic equation?

parabola

200

What makes a quadratic equation quadratic?

the x²

300

How do you know if an equation has a min or max?

By looking at the leading coefficient. If its positive, it has a min. If its negative, it has a max 

400

What is the equation for the axis of symmetry?

x=-b/2a

500

What is the turning point on a parabola called?

vertex

Find it

100

What is the y-intercept of y= -2x²+12x-7?

-7

200

What is the axis of symmetry of y= -2x²+12x-7?

x=3

300

What is the vertex of y= -2x²+12x-7?

(3,11)

400

Does y= -2x²+12x-7 have a min or max?

max

500

What is the maximum value of y= -2x²+12x-7?

11

Solving Quadratic Equations

100

Solve x²-5x+4=0

x=4,1

200

solve x²+10x=-25

x=-5

300

What is the square root of 36?

6 and -6

400

Solve 2x²=8

x=2,-2

500

Solve 4x²+10=11

x= 1/2 and -1/2