Transcript What you need to be able to do

Variables, Functions, Patterns and
Graphs
What you need to be able to do:
Transform English phrases into mathematical
expressions and equations
1.“x is 5 more than 2 times n”
Write an equation to model this relationship.
x = 2n + 5
2.Define the variable and write an equation to model
the relationship in the table
You MUST know your order of operations
PEMDAS
Classifying numbers
You need to know the difference between:
rational/irrational/natural numbers/whole numbers/integers
You MUST know your basic number skills
and the properties of real numbers:
Patterns & Functions
Terms you need to know:
Domain: the possible values for x
Range: the possible values for y
Independent variable: the variable that you change. It
is plotted on the x-axis
Dependent variable: it is plotted on the y-axis
Know how to graph functions – which axis is the
independent variable and which is the dependent?
The price of a turkey depends on its weight. This week
turkeys are selling for $1.60 per lb
a) Write a rule to describe the function
C = 1.6x where x is the # pounds of turkey bought
b) What is the price of a 15lb turkey?
1.6 x 15 = $24
c) How many pounds could you buy for $12?
12/1.6 = 7.5lb
d) Plot a graph of the function
x-axis = # of pounds, y –axis = Cost
Regents Practice Questions
1. Which expression represents “5 less than twice x”?
(1) 2x – 5
(3) 2(5 – x)
(2) 5 – 2x
(4) 2(x – 5)
2. Which verbal expression is represented by ?
1)
twice the sum of a number and four
2)
the sum of two times a number and four
3)
two times the difference of a number and four
4)
twice the product of a number and four
3. If n is an odd integer, which equation can be used to find
three consecutive odd integers whose sum is ?
1)
2)
3)
4)
4. Carol plans to sell twice as many magazine subscriptions as
Jennifer. If Carol and Jennifer need to sell at least 90
subscriptions in all, which inequality could be used to
determine how many subscriptions, x, Jennifer needs to sell?
1)
2)
3)
4)
5. Mr. Stanton asked his students to write an algebraic
expression on a piece of paper. He chose four students to go
to the board and write their expression.
Robert wrote:
Meredith wrote:
Steven wrote:
Cynthia wrote:
Which student wrote an algebraic expression?
1) Robert 2) Meredith 3) Steven 4) Cynthia