helpful hints to help you with graphs of quadratic functions foldable and quadratic equations...

Helpful hints to help you with Graphs of Quadratic Functions

foldable and Quadratic Equations Matching Activity

Use your foldable on page 18 and angry birds warm-up on page 28.

A

B

C

D G

H

I

E

F

1

2

3

4 7

8

9

5

6

Hints:1.Factor the quadratic equation to find the roots.2.Find the roots on the graph.3. Use foldable on pg. 18 to help.

I will do problem #1 as an example on the next slide.

x2 – 3x – 4 = 0(x – 4)(x + 1) = 0 x = 4 x = -1

roots

8

x = -1 x = 4

Work shown on page 31 - 32

How to find the axis of symmetry?Use the axis of symmetry formula

x = 1.5

y = x2 – 3x – 4y = (1.5)2 – 3(1.5) – 4y = -6.25

Vertex: (1.5, -6.25)

How to find the Vertex?Substitute “x” into the quadratic equation to get “y”

Look at the foldable on page 18 to help

(1.5, -6.25)

(1.5, -6.25)x = 1.5

Hints:1.Find the roots on the graph.2. Work backwards to get the equation.Use angry birds warm-up on pg. 28 and foldable on page 18 to help

I will do problem #3 as an example on the next slide.

x = 0 x = 2

{0, 2}

(1, -1)

(1, -1)

x = 1

x = 1

Min (lowest point)(0, 0)

x = 0 x = 2x(x – 2) = 0x2 – 2x = 0

Equation needs to be in standard form y = ax2 + bx + c

y = x2 – 2x (check with graphing calculator…I know, so much work )

y = x2 – 2x Letter E roots are in between so use the equation strips to help you find the answer. It’s like a puzzle…