Transcript Evaluating_Expressions_page_2.ppt

Evaluating Expressions
Real World Examples
Page 2 & 4 in Practice Workbook
Page 2, #22
A side table has interior storage space in the
shape of a cube. What is the volume of
the storage space if the interior length is
12 inches?
V = Bh
V = lwh
V = (12)(12)(12)
V= 1728
Page 2, #23
There are 52 playing cards in a standard
deck of playing cards. You are combining
decks of cards so that you can play ba
game with a large number of people. The
expression 52d represents the number of
cards in d decks. If you combine 4 decks
of cards, ow manu cards will you have all
together?
52d
52(4) = 208 cards
Page 2, #24
An item costs c dollars and 6% sales tax is
charged. The total cost including sales tax
is given by the expression 1.06c. You are
buying a skateboard that costs $75. What
is the cost of the skateboard including
sales tax?
1.06c
1.06 (75) = $79.50
Page 4, #24
Three weeks ago, an art supply store started
selling a paint kit for 75% of the original
price. Now the kit is 15% off of the sale
price. The expression
.75x – 0.15(0.75x)
represents the current price of the paint kit
where x is the kit’s original price (in
dollars). Find the current price if the kit
originally cost $48
Page 4, #24 (continued)
.75x – 0.15(0.75x)
.75 (48) – 0.15(0.75)(48)
36 – 5.4
30.6
Since this is money, we say
$30.60
Page 4, #25
You are decorating the perimeter of the
ceiling of your living room with crown
molding. The expression 2x + 2y
represents the total amount of molding you
need where x is the width of the room (in
feet) and y is the length of the room (in
feet). Find the total amount of wood you
need if the room is 11 feet wide and 10.5
feet long.
Page 4, #25 (continued)
2x + 2y
2(11) + 2 (10.5)
22 + 21
43 inches
Evaluating Expressions
“Self Check”
1.
Login to Moodle: moodle.nisdtx.org
2.
Go to your Algebra I – L.Tatum site
Click the first Homework link
Take the Self Check
Save it when you finish
3.
4.
5.
Translating
Let’s look at translating verbal
phrases into expressions
The difference of 9 and a
number n
9-n
The product of 9 and a
number n
9n
A number decreased by 4
n-4
15 more than a number
15 + n
Three times the sum of 8
and a number
3(8+n)
25 more than twice a
number m
For More Practice
Use the Animated/ Interactive
activity in Classzone
Words for Operators
We discovered that many different
words are used to indicate
operations.
•Create this table in your notebook
•Think of all the “other words” we could use to mean
the same thing
Add
Increase sum plus total all
together
Subtract
Decrease difference
Less than (switch)
Lower
descend
Multiply
Product
OF
times
Double or twice (x2)
Divide
Quotiient
share
Half (divide by 2)
minus less
equally divide