arelationthatassignsexactlyoneoutput(range)valueforeachinput(domain)value.

asetoforderedpairs

alloftheinputvalues

alloftheoutputvalues

throughmorethanonepointofthegraphthenforsomevalueofxthereismorethanonevalueofy.Therefore,therelationisnotafunction.

ifanyverticallinepasses

anequationthatdescribesafunction.

whenf(x)isusedtoindicatetheoutputs.Youreadf(x)as“fofx”or“fisafunctionofx.”

theinput(x)valuesofthefunction.Theyaregraphedonthehorizontalaxis.

theoutput(y)valuesofthefunction.Theyaregraphedontheverticalaxis.

-2

0

4

10

-31

921

-3

0

2

5

4-2

-6-12

Aplumberchargesa$30feetovisitajoband$25perhourfortheworkhedoesthere.Writearuletodescribethethetotalcostofhisvisitasafunctionofthenumberofhoursspentworkingatthesite.