1

Sect.7.1GraphingQuadraticEquationsInchapter6westudiedquadraticfunctionandtheirgraphs.Wecannowalgebraicallydeterminetheinterceptsofaquadraticfunction bysolvingtheequation

Knowingtheinterceptsallowsustomorepreciselygraphafunction.

Example1:

Graph

Findthecoordinatesofthevertex:

Statethecoordinatesoftheintercept:

Findthecoordinatesoftheinterceptsbyfactoringorquadraticformula:

Theinterceptsaresolutionstotheequation

.

10 8 6 4 2 0 2 4 6 8 10

10987654321

12345678910

x

y

2

Example2:

Graph

.

.

10 8 6 4 2 0 2 4 6 8 10

151413121110987654321

1234

x

y

3

Example3:

Graph

.

10 8 6 4 2 0 2 4 6 8 10

10987654321

12345678910

x

y

4

Remember:

Thexinterceptsofthegraph,orthezerosofaquadraticfunctioncorrespondtotherootsofthequadraticequation.

Forexample:Findtherootsoftheequationx27x+12=0Findthezerosoff(x)=x27x+12Findthexinterceptsofy=x27x+12

Example4:

Graph

10 8 6 4 2 0 2 4 6 8 10

10987654321

12345678910

x

y

5

Attachments

PM117s1.gsp

pm7s1p8.tns

7s1e1finalt.mp4

7s1e2finalt.mp4

7s1e3finalt.mp4

pm7s1p1.tns

pm7s1p2.tns

PM117s12.gsp

SMART Notebook

SMART Notebook

SMART Notebook

SMART Notebook

SMART Notebook

SMART Notebook

SMART Notebook

SMART Notebook

Page 1Page 2Page 3Page 4Page 5Attachments Page 1