Stallion Starter
Evaluate each algebraic expression for the
given value of the variables.
1. )
7x + 4 for x = 6
2.)
8y – 22 for y = 9
3.)
12x 8+
4.)
y + 3z for y = 5 and z = 6 23
y
46
50
for x = 7 and y = 4
86
Writing Algebraic
Expressions
Objective:
Be able to write an algebraic
expression for a word phrase or write a
word phrase for an expression.
Although they are closely
related, a Great Dane weighs
about 40 times as much as a
Chihuahua.
An expression for the weight of the
Great Dane could be 40c, where c is the
weight of the Chihuahua.
When solving real-world problems, you will need
to translate words, or verbal expressions, into
algebraic expressions.
Notes
In order to translate a word
phrase into an algebraic
expression, we must first
know some key word
phrases for the basic
operations.
Notes:
Addition
Subtraction
Multiplication
Division
Addition Phrases:
More than
Increase by
Greater than
Add
Total
Plus
Sum
Subtraction Phrases:
Decreased by
Difference between
Take Away
Less
Subtract
Less than*
Subtract from*
Multiplication Phrases:
Product
Times
Multiply
Of
Twice or double
Triple
Division Phrases:
Quotient
Divide
Divided by
Split equally
Notes
Multiplication expressions should
be written in side-by-side form,
with the number always in front of
the variable.
3a
2t
1.5c
0.4f
Notes
Division expressions should be
written using the fraction bar
instead of the traditional
division sign.
Guided Problems



Addition phrases:
3 more than x
the sum of 10 and a number
c
a number n increased by 4.5
Guided Problems
Subtraction phrases:

a number t decreased by 4


the difference between 10 and a
number y
6 less than a number z
Guided Problems

Multiplication phrases:
the product of 3 and a number
t

twice the number x

4.2 times a number e
Guided Problems
Division phrases:

the quotient of 25 and a number b

the number y divided by 2

2.5 divide g
Guided Problems
Mr. Nehru bought two adult tickets and three student
tickets for the planetarium show. Write an algebraic
expression that represents the cost of the tickets.
Let a be the cost of the adult tickets
Let c be the cost of the student tickets
The cost of the tickets is represented by 2a + 3c
Guided Problems
It takes Earth about 365 days to orbit the
Sun. It takes Uranus about 85 times as
long. Write an Algebraic and a numeric
expression to describe the number of days
it takes Uranus to orbit the Sun.
Let e be the number of days it takes Earth to orbit the Sun.
Let u be the number of days it takes Uranus to orbit the Sun.
Earth
Uranus
Algebraic
Numeric
e
85 times e
85e
85(365) =31,025 days