Algebra 1 Common Core Student Edition, Grade 8-9

Graphing a

Function Rule

Co m m o n Co r e St at e St a n d a r d s

F-IF.B.5 Relate the dom ain o f a function to its graph

and, where applicable, to the qu an tita tive relationship it

describes... Also N-Q.A.1, A-REI.D.10

M P 1, M P 2, M P 3, M P 4

Object ive To graph equations that represent functions

You g e t to choose

th e inform ation

you use!

f| ', Getting Ready!

Yo u a r e p ay i n g t o p r i n t p i c t u r e s f r o m

your digital cam era at t he photo shop.

You choose one size f o r all your p rint s.

What is one possible graph of the

relationship between the total cost and

the number of pictures you print?

MATHEMATICAL

PRA CTI CES

Lesso n
Vocabulary
continuous graph
discrete graph

Y o u c a n u s e a t a b le o f v a lu e s t o h e lp y o u m a k e a g r a p h i n t h e S o lv e It.

Esse n t i a l U n d e r st a n d i n g The set o f all solutions o f an equation form s the

e q u a t io n ’s g r a p h. A g r a p h m a y in c lu d e s o lu t io n s t h a t d o n o t a p p e a r i n a t a b le. A

r e a l- w o r ld g r a p h s h o u ld o n ly s h o w p o in t s t h a t m a k e s e n s e i n th e g iv e n s it u a t io n.

jjhink

What input values

make sense here?

It is possible to use any

input x in the equation

and get an output y.

Choose integer values

ofxto produce integer

values o fy , which are

easier to graph.

Pr o b l em 1 Gr ap h in g a Funct ion Rule

What is the graph of the function rule y = — 2x + 1?

Step 1 Make a table of values. Step 2 Graph the ordered pairs.

-1

0

1

2

y:

y:

y:

-2 (—1) + 1 = 3

-2(0) + 1 = 1

• 2 ( 1 ) + 1 = -1

y = -2(2) + 1 = - 3

(-1, 3)

(0,1)

(1, - D

(2, - 3 )

y

i\ X

(^0) i
i

• 
  

  C onnect th e p o in ts w ith a line
  to represent all solutions.
  Go t I t? 1. W h a t is t h e g r a p h o f th e f u n c t i o n r u le y = | x — 1?
  c
  PowerAlgebra.com

  
  

  Lesson 4 -4 G ra p h in g a F u n c tio n R ule 253
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