1. Writing Expressions

2. What is an Algebraic Expression?
An algebraic expression contains at least one variable and at least one operation.
Examples: a 4x
c- 5
𝑦 5

3. What is a Variable? A variable is a letter that stands for a number.
**ANY letter can be used as a variable.**
*The letter x is most often used.
Example: a x y

4. What is a Term?
A term is a number, a variable, or a product or quotient of numbers and variables.
Example: 3 a 3a
3 𝑎

5. What is a Coefficient?
A coefficient of a term is the number in front of the variable.
Example: 3a (3 is the coefficient)
4b (4 is the coefficient)
7x (7 is the coefficient)

6. Parts of an Expression Work with your table group to complete chart in your notes.
Coefficients
Variables
Exponents
8c2 9x y8
12a2b3

7. Addition
sum
more than
total
plus
increased by

8. Examples of Addition Expressions
17 more than x
n more than 18
A number increased by 17
18 increased by a number
The total of a number and 17
The total of 18 and a number
x plus 17
18 plus n
The sum of x and 17
The sum of 18 and n

9. 17 more than x
x + 17
n more than 18
18 + n

10. Click the correct match1
Click the correct match
10 more than x
10 + x
x + 10

11. Click the correct match2
Click the correct match
x plus 25
25 + x
x + 25

12. Click the correct match3
Click the correct match
50 increased by x
50 + x
x + 50

13. Click the correct match4
Click the correct match
the total of 17 and a number
n + 17
17 + n

14. Click the correct match5
Click the correct match
the sum of c and 7
7 + c
c + 7

15. Subtraction
difference
less than
less
minus
decreased by

16. Examples of Subtraction Expressions
subtract 17 from a number
subtract a number from 18
17 less than x
n less than 18
a number minus 17
18 minus a number
a number decreased by 17
18 decreased by a number
the difference of x and 17
the difference of 18 and n
x less 17
18 less n

17. x - 17 18 - n 17 less than x n less than 18 subtract a number from 18
subtract 17 from a number
18 - n
n less than 18
subtract a number from 18

18. Choose the correct match6
Choose the correct match
Subtract c from 12
c - 12
12 - c

19. Choose the correct match7
Choose the correct match
45 less than n
n - 45
45 - n

20. Choose the correct match8
Choose the correct match
10 decreased by r
10 - r
r - 10

21. Choose the correct match9
Choose the correct match
the difference of 60 and p
p - 60
60 - p

22. Choose the correct match10
Choose the correct match
75 less x
x - 75
75 - x

23. Helpful Tip:
When adding or subtracting a number from the variable, put the number and variable in the order of the words UNLESS the phrase contains the word than, from, or added to. Then you move the number you are adding or subtracting to the end of the expression.
Ex. 6 more than p = p + 6
5 added to p = p + 5
5 from r = r - 5

24. Multiplication
product
times
twice

25. Multiplication Expressions
To avoid confusion with the “x” (multiplication) symbol, there are other ways to show multiplication.
We will place the coefficient in front of the variable with no symbol.

26. They should be written in side-by-side form with the number (coefficient) always in front of the variable. 3a 2t 1.5c 0.4f

27. 50n Examples of Multiplication Expressions 50 multiplied by n
50 times a number
The product of 50 and a number

28. Division
quotient
divide

29. Division Expressions
They should be written with the fraction bar for division instead of the division symbol. 𝑦 8 3 𝑡

30. Examples of Division Expressions
7 𝑛
𝑡 5
A number divided by 5
7 divided by a number
The quotient of 7 and n
The quotient of t and 5
Divide a number by 5
Divide 7 by n

31. Choose the correct match
8 times a number
8 𝑐 8c

32. Choose the correct match
The product of 12 and n
12 𝑛
12n

33. Choose the correct match
twice the number
2 𝑐 2c

34. Choose the correct match
The quotient of 60 and a number
60 𝑛
𝑛 60

35. Choose the correct match
50 divided by x
50 𝑥
𝑥 50

36. Choose the correct match
divide y by 75
75 𝑦
𝑦 75

38. Write the expression
y increased by 20
y + 20
Answer

39. Write the expression
x less than 90
Answer
90 - x

40. Write the expression
Twice a number
Answer 2n

41. Write the expression
10 decreased by n
Answer
10 - n

42. Write the expression
80 divided by p
Answer
80 ÷ p

43. Write the expression
x more than 12
12 + x
Answer

44. Write the expression
the product of 21 and m
Answer
21m

45. Write the expression
The quotient of x and 9
Answer
x ÷ 9

46. Write the expression
Subtract 15 from n
Answer
n - 15

47. Write the expression
The difference of y and 40
Answer
y - 40

48. Write the expression
The sum of 25 and a number
25 + n
Answer

49. the difference between a number and 30 A number divided by 14
EXIT TICKET
Write an algebraic expression for each of the following:
the difference between a number and 30
A number divided by 14
The quotient of 56 and y
18 more than x
The product of 78 and n

50. Writing Algebraic Expressions from Word Problems
𝑡 5

51. Writing Algebraic Expressions
Write each phrase as an algebraic expression.
Eight dollars more than Ryan earned.
Step 1: Define a variable (What is the unknown?)
r = Ryan’s earnings
Step 2: Substitute variable for what Ryan earned in original problem. (What are we doing to Ryan’s earnings?)
r + 8

52. Frank is a marathon runner
Frank is a marathon runner. Write an expression to show the number of miles Frank ran if he completed 7 marathons.
Answer 7x

53. Rhonda is 5 inches shorter than Anna
Rhonda is 5 inches shorter than Anna. Write an expression for Rhonda’s height.
Answer
h - 5

54. Hank bought 4 movie tickets
Hank bought 4 movie tickets. Write an expression to show how much he paid for the tickets.
Answer 4x

55. Dan had some horses and 2 stables
Dan had some horses and 2 stables. Write an expression to show how many horses he put in each stable.
Answer
𝑥 2

56. In the school cafeteria, there are 40 small tables and some large tables. Write an expression to find the total number of tables.
Answer
40 + n

57. Jill paid a certain amount for the bike and $5. 00 for shipping
Jill paid a certain amount for the bike and $5.00 for shipping. Write an expression to show the total cost she paid.
Answer
b + 5

58. At the store, Dana bought some shoes on sale
At the store, Dana bought some shoes on sale. Then she used her coupon for $10.00 off. Write an expression to show what she paid.
Answer
n -10

59. Mrs. Brown bought 20 pencils. Her students used some pencils
Mrs. Brown bought 20 pencils. Her students used some pencils. Write an expression to show how many pencils are left.
Answer
20 - x

60. Karen has 125 shells. She places n in each box
Karen has 125 shells. She places n in each box. Write an expression to show the amount of shells in each box.
Answer
125 𝑛

61. Six years less than Tracey’s age
EXIT TICKET
Define a variable then write an algebraic expression that represents the following situation:
Six years less than Tracey’s age
Two less than one-third of the points that the Panthers scored

62. Six feet less than the width
EXIT TICKET
Define a variable then write an algebraic expression that represents the following situation:
Six feet less than the width
Four hours more per week than Theo studies