1. 8x - 5 -2d + 5 We will add and subtract expressions.
Learning Objective
NAME_________________ PER. ____
We will add and subtract expressions.
We will combine “like terms”.
What are we going to do?
CFU
Activate Prior Knowledge
Identify variable terms1 (underline each including their sign) and constant terms2 (circle each including their sign) in the expressions.
8x - 5
1. 3x x - 11
1 VARIABLE terms
2 CONSTANT terms
Vocabulary
2. 4d d - 5
-2d + 5
Students, you already know how to identify variable terms and constant terms in an expression. Now, we will identify like terms in an expression to add and subtract expressions.
Make Connection

2. (2x + 6) + (3x + 12 ) 5x + 18 (4d + 10) - (3d + 5) 1d + 5
Concept Development
Like terms are terms with the same variables raised to the same power.
Adding and subtracting expressions is to combine1 like terms.
Adding and subtracting expressions produces2 equivalent3 expressions.
Adding and Subtracting Expressions
(2x + 6) + (3x + 12) and 5x + 18 are
equivalent expressions.
(2x + 6) + (3x + 12 )
5x + 18
2x and 3x are like terms.
6 and 12 are like terms.
Which terms will be added together when adding the expressions (3y + 9) + (5y - 11)?
How do you know?
A 3y + 5y
B 3y + 9
C (-11)
D 5y + (-11)
CFU
(4d + 10) - (3d + 5) and 1d + 5 are
equivalent expressions.
(4d + 10) - (3d + 5)
1d + 5
4d and 3d are like terms.
10 and -5 are like terms.
1 put together
2 makes
3 equal value
Vocabulary

3. 10a + 17 7y + 14 16d - 12 13p - 3 3x and -5x 6 and -11 3a + 9 2y + 4
Skill Development/Guided Practice
Adding and subtracting expressions is to combine like terms.
Adding and subtracting expressions creates equivalent expressions.
Rewrite the addition or subtraction problem vertically. Hint: Line up like terms.
Combine like terms. Hint: Add or subtract each like term.
Interpret4 equivalent expressions. “____ is equivalent to ____”
Add and subtract expressions. 1 2 3
How did I/you rewrite the expressions?
How did I/you combine like terms?
CFU 1 2
Like Terms
3x and -5x
6 and -11
1. (3a + 9) + (7a + 8)
2. (2y + 4) + (5y + 10)
3. (5d - 7) + (11d - 5)
4. (4p - 9) + (9p + 6)
3a + 9
2y + 4
7a + 8
5y + 10
10a + 17
7y + 14
5d - 7
4p - 9
+ 11d - 5
+ 9p + 6
16d - 12
13p - 3
4 explain
Vocabulary

4. 3x and -5x 6 and -11 6m + 2m + 4m 6n + 7n + 8n -5 + 9 + 4 3 + 1 - 2
Skill Development/Guided Practice (continued)
Adding and subtracting expressions is to combine like terms.
Adding and subtracting expressions creates equivalent expressions.
Rewrite the expressions as the sum of all terms.
Identify like terms in the expressions. (underline and circle)
Combine like terms. Hint: Add each like term.
Interpret equivalent expressions. Hint: Answer the question.
Add and subtract expressions. 1 2 3 4
How did I/you rewrite the expressions?
How did I/you identify like terms?
How did I/you combine like terms?
CFU 1 2 3
5. What is the perimeter5 of the trapezoid?
__________________________________________________________________
6. What is the perimeter of the triangle?
Like Terms
3x and -5x
6 and -11
2m - 5
6n + 3 6m 9
7n + 1
4m + 4
8n - 2
(2m - 5) + (9) + (4m + 4) + (6m)
(6n + 3) + (7n + 1) + (8n - 2)
What are my variables?
What are my constants?
6m + 2m + 4m
What are my variables?
What are my constants?
6n + 7n + 8n
The perimeter of the trapezoid is ______________
The perimeter of the triangle is ______________
5 distance around
Vocabulary

5. 3x and -5x 6 and -11 3m + 1 + 4m ANSWER: 8m combine like terms
Adding and subtracting expressions is to combine like terms.
Adding and subtracting expressions creates equivalent expressions.
Skill Closure
Rewrite the expressions as the sum of all terms.
Identify like terms in the expressions. (underline and circle)
Combine like terms. Hint: Add each like term.
Interpret equivalent expressions. “____ is equivalent to ____”
Add and subtract expressions. 1 2 3 4
Like Terms
3x and -5x
6 and -11
1. (-3z - 1) + (6z + 9)
u u - 1
-3z + (-1) + (6z) + 9
11u (-9u) + -1
Access Common Core
Word Bank
combine
like terms
equivalent
expressions
Jasmine made an error in adding the expressions below. Describe and correct the error she made.
What was the mistake and why do you think Jasmine did wrong? ________________________________________________________________________________________________________________________________
3m m
ANSWER: 8m
Summary Closure
What did you learn today about adding and subtracting expressions? (Pair-Share)
Use words from the word bank.

6. 3x and -5x 6 and -11 The perimeter of the triangle is ____________
Independent Practice
Adding and subtracting expressions is to combine like terms.
Adding and subtracting expressions creates equivalent expressions.
Rewrite the expressions as the sum of all terms.
Identify like terms in the expressions. (Underline Variables and Circle Constants)
Combine like terms. Hint: Add each like term.
Interpret equivalent expressions. Hint: “____ is equivalent to ____” or Answer the question.
Add and subtract expressions. 1 2 3 4
Like Terms
3x and -5x
6 and -11
1. (12k - 9) + (2k + 5)
2. (10h + 12) - (7h - 3)
3. (8d + 1) - (13d + 3)
4. (9b + 5) + (-7b - 1)
5. What is the perimeter of the triangle?
_____________________________________________
12k + (-9) + 2k + 5
10h (-7h) + 3
“12k – 9 + (2k + 5) is equivalent to ________
“10h + 12 – (7h – 3) is equivalent to _________
8d (-13d) + (-3)
9b (-7b) + (-1)
“8d + 1 – (13d + 3) is equivalent to ________
“9b (-7b – 1) is equivalent to _________
3n - 2
2n - 10
n + 13
(n + 13) + (2n - 10) + (3n - 2)
The perimeter of the triangle is ____________

7. NAME ________________________ Period ________
Homework
NAME ________________________ Period ________
SHOW ALL WORK. Underline and Circle Terms.
1. 7b (6b + 3)
2. 6c (-4c - 7) - (-9c + 3)
3. (9f + 8) - (5f - 12)
4. (9q - 3) - (6q + 11)
5. 2k (13k - 2)
7. 8y (-2y) + (-8)
x x x - 6
h h - 1

8. Remember to underline and circle terms.
HOMEWORK
2m - 1
2m + 5 3m 5
1. What is the perimeter of the quadrilateral?
__________________________________________________
Remember to underline and circle terms.
The perimeter of the quadrilateral is ____________
Access Common Core
1. Choose Yes or No to indicate whether each expression is equivalent to 20h + 12.
A (18h + 12) + 2h
B (13h - 3) + (7h + 15)
C (17h + 6) - (-3h) + 6
O Yes O No
2. Choose Yes or No to indicate whether each expression is equivalent to -18p + 9.
A (-14p + 9) + 2p
B (-7p - 1) + (-11p + 10)
C (-13p + 5) - (5p + 4)
O Yes O No
3. Choose Yes or No to indicate whether each expression is equivalent to 5d - 11.
A 13d d + 8
B -6d d - 7
C 8d d
O Yes O No
Describe and correct each error made in adding and subtracting expressions below.
Describe the mistake and correct the answer: ____________________________________________________________________________________________________________________
x x + 3
Answer Given: -9x – 23