Transcript 1-2 Modeling Relationships with variables

WARM UP
Find the mean, median, and mode of the
following set of numbers:
10, 1, 3, 6, 4, 3, 7
EXAMPLE
One Direction is designing a stage to use in its new music video. Their
set designer made the sketches shown below.
# of sides
# of triangular
regions
3
4
5
6
1
1) Complete the table.
2) What is the relationship between the number of sides a stage has
and the number of triangle regions created by the line segments?
3) One Direction plans to use a 12-sided stage. How many triangular
regions can the designer form with the segments starting at one
corner?
DEFINITIONS
Variable– A letter that represents a number. The
value of a variable can change. (2x + 6)
Variable Expression – Mathematical phrase that
uses numbers, variables, and operation
symbols.
Term – A number, variable, or the product or
quotient of a number and a variable
EXAMPLE
b
7a + - 5
2
1)Could you use a letter other than a or b?
2)How many terms does the expression have?
3)How many terms does the expression s – 2 have?
EXAMPLE
Each chicken burrito at Chipotle costs $6.25.
a) Write an equation you can use to find the total cost
when you know the number of burritos bought.
b) What do the variables represent?
c) A worker says 2 burritos cost $62.52. What is the
mistake he made?
EXAMPLE
Write an equation for the data in the table.
c = cost of items purchased
a = amount of change.
Change from a $20 bill
Cost of Items
Purchased
$20.00
$19.00
$17.50
$11.59
Amount of
Change
$0
$1.00
$2.50
$8.41
*Suppose you wrote “The
cost of the items plus the
amount of change equals
$20. Write an equation.
CLASSWORK
P. 13-14 # 1, 3, 7, 9, 11, 13, 32, 33
HOMEWORK
P. 13-14 #2, 4, 6, 8, 10, 14, 16, 20,
21, 22, 30, 31