2-3 translating between words and math 16 36 19 4 x evaluate each expression for x = 9. 1. 7 + x 2....
TRANSCRIPT
2-3 Translating Between Words and Math
16
36
19
4x
Evaluate each expression for x = 9.
1. 7 + x
2. 4x
3. 2x + 1
4. 36
Problem of the Day
2-3 Translating Between Words and Math
In word problems, you may need to identify the action to translate words into math.
Action Operation
Put together or combine
Find how much more or less
Put together groups of equal parts
Separate into equal groups
Add
Subtract
Multiply
Divide
2-3 Translating Between Words and Math
Lake Superior is the largest lake in North America. Let a stand for the area in square miles of Lake Superior. Lake Erie has an area of 9,910 square miles. Write an expression to show how much larger Lake Superior is than Lake Erie.
Additional Example 1A: Social Studies Application
To find how much larger, subtract the area of Lake Erie from the area of Lake Superior.
a – 9,910
Lake Superior is a – 9,910 square miles larger than Lake Erie.
2-3 Translating Between Words and Math
Let p represent the number of colored pencils in a box. If there are 26 boxes on the shelf, write an algebraic expression to represent the total number of pencils on the shelf.
To put together 26 equal groups of p, multiply 26 times p.
26p, or 26 • p
There are 26p pencils on the shelf.
Additional Example 1B
2-3 Translating Between Words and Math
The salary of the governor of Florida for the 2008–2009 fiscal year is $132,932. This is d dollars more than Leones makes as a landscaper. Write an expression for Leones’ salary.
Check It Out: Example 1A
132,932 - d
2-3 Translating Between Words and Math
Check It Out: Example 1B
A group of n friends go to the movies. They purchase adult tickets for $38. Write an expression for the price of one adult ticket.
38 ÷ n or 38n
2-3 Translating Between Words and Math
Check It Out: Example 1C
Beth has a pet cat named Buddy. In 3 years, Buddy will be b years old. Beth got Buddy when he was 2 years old. Write an expression that represents how many years Beth has had Buddy.
b - 5
2-3 Translating Between Words and Math
37 + 28
• 28 added to 37
• 37 plus 28
• the sum of 37 and 28
• 28 more than 37
• 28 added to x
• x plus 28
• the sum of x and 28
•28 more than x
x + 28
++Operation
Numerical Expression
Words
Algebraic Expression
Words
There are several different ways to write math expressions with words.
2-3 Translating Between Words and Math
• 12 subtracted from k
• k minus 12
• the difference of k and 12
• take away 12 from k
k — 12
Operation
Numerical Expression
Words
Algebraic Expression
Words
90 — 12
• 12 subtracted from 90• 90 minus 12• the difference of 90 and 12• 12 less than 90• take away 12 from 90
2-3 Translating Between Words and Math
• 8 times w• w multiplied by 8• the product of 8 and w• 8 groups of w
8 w or (8)(w) or 8w
Operation
Numerical Expression
Words
Algebraic Expression
Words
8 48 or 8 48
• 8 times 48• 48 multiplied by 8• the product of 8 and 48
or (8)(48) or
8(48) or (8)48
2-3 Translating Between Words and Math
• n divided by 3
• the quotient of n and 3
n 3 or
Operation
Numerical Expression
Words
Algebraic Expression
Words
327 3 or
• 327 divided by 3• the quotient of 327 and 3
3273
n3
2-3 Translating Between Words and Math
Write each phrase as a numerical or algebraic expression.
Additional Example 2: Translating Words into Math
A. 987 minus 12
987 12
B. x times 45
45 • x or 45x
2-3 Translating Between Words and Math
Write each phrase as a numerical or algebraic expression.
Check It Out: Example 2
312 + 58B. the quotient of 21 and 10
2110
21 ÷ 10 or
A. 312 plus 58
2-3 Translating Between Words and Math
Write each phrase as a numerical or algebraic expression.
Check It Out: Example 2 continued
5 x
D. t minus 15
C. 5 times x
t - 15
2-3 Translating Between Words and Math
Write two phrases for each expression.
Additional Example 3: Translating Math into Words
A. 16
• 16 divided by b
B. (75)(32)
• 75 times 32
• the quotient of 16 and b
• the product of 75 and 32
b__
2-3 Translating Between Words and Math
Check It Out: Example 3
A. The Nile River is the world’s longest river. Let n stand for the length in miles of the Nile. The Paraná River is 3,030 miles long. Write an expression to show how much longer the Nile is than the Paraná.n - 3,030
B. Write the phrase as a numerical or algebraic expression.42 more than 79
79 + 42
2-3 Translating Between Words and Math
Check It Out: Example 3 continued
C. Write two phrases for the expression.18 - r
r less than 18
the difference of 18 and r
2-3 Translating Between Words and Math
Standard Lesson Quiz
Lesson Quizzes
Lesson Quiz for Student Response Systems
2-3 Translating Between Words and Math
1. Let x represent the number of minutes Kristen works out in one week. Write an expression for the number of minutes she works out in 4 weeks.
Lesson Quiz
Write each phrase as a numerical or algebraic expression. 2. 7 less than x
3. The product of 12 and w
4x
x 7
12w
x more than 17 or x added to 17
n divided by 12 or the quotient of n and 12
Write a phrase for each expression. 4. 17 + x
5. n 12
2-3 Translating Between Words and Math
1. Tim has 15 more cartoon CDs than Martin has. If n represents the number of CDs Martin has, identify an expression for the number of CDs Tim has.
A. n + 15
B. n – 15
C. 15n
D. n 15
Lesson Quiz for Student Response Systems
2-3 Translating Between Words and Math
2. Which of the following represents the given phrase as a numerical or algebraic expression?
35 more than n
A. n + 35
B. n – 35
C. 35n
D. n 35
Lesson Quiz for Student Response Systems
2-3 Translating Between Words and Math
3. Which of the following represents the given phrase as a numerical or algebraic expression?
the quotient of w and 26
A. w + 26
B. w – 26
C. 26w
D. w 26
Lesson Quiz for Student Response Systems
2-3 Translating Between Words and Math
4. Identify two phrases for the expression
k – 11.
A. 11 added to k or 11 more than k
B. 11 subtracted from k or 11 less than k
C. 11 added to k or 11 less than k
D. 11 subtracted from k or 11 more than k
Lesson Quiz for Student Response Systems