Harrisburg School District
Pre-Algebra
Chapter Two (Prentice Hall)
Lesson 2-3
Essential Question:
How are variable expressions simplified?
Activating Strategies: (Learners Mentally Active)
Combining Like Terms Game. Distribute various amounts of colored paper. (Keep
record of colors given to determine combination). Teacher writes on the board:
3 blue + 4 yellow. Student with 1 blue and 1 yellow must find the student with 2 blue
and 3 yellow to satisfy the expression 3 blue + 4 yellow. Teacher will continue to give
combinations which students must match.
Acceleration/Previewing: (Key Vocabulary)
constant, term, like terms, coefficient
Teaching Strategies: (Collaborative Pairs; Distributed Guided Practice;
Distributed Summarizing; Graphic Organizers)
In collaborative pairs, What criteria did you use to make your combinations? (like
colors combined)
Use color tiles to model like terms. Practice modeling and simplifying.
Distribute color tiles to students for practice.
Complete graphic organizer.
Distributed Guided Practice/Summarizing Prompts: (Prompts Designed to
Initiate Periodic Practice or Summarizing)
In pairs, use graphic organizer to work problems on 2-3 worksheet.
Complete 2-3 worksheet for homework.
Summarizing Strategies: Learners Summarize & Answer Essential Question
Ticket-Out-The-Door: Answer the essential question: “How are variable expressions
simplified?”
clk/C:/My Documents/LF Acquisition Lesson Plan (2/8/07)
Lesson 2-3
2.3 Graphic Organizer
Simplifying Variable Expressions
Name___________________________ Period____ Date__________________
Simplify the variable expression; 2 – 3x – y + 6x – 4y + 6
Steps in Words
Steps in Mathematics
Write down the problem
2 – 3x – y + 6x – 4y + 6
Combine coefficients of x
2 + (-3x + 6x) – y – 4y + 6
2 + 3x – y – 4y + 6
Combine coefficients of y
Combine constants
2 + 3x + (-y – 4y) + 6
2 + 3x + (-5y) + 6
2 + 3x – 5y + 6
(2 + 6) + 3x – 5y
8 + 3x – 5y
Your turn: Simplify the variable expression; 2x – 7y – 6x + 8 – 5 + 12y
Steps in Words
Write down the problem
Combine coefficients of x
Combine coefficients of y
Combine constants
How are variable expressions simplified?
Lesson 2-3
Steps in Mathematics
Name: __________________________________
Date: _____________
Identifying Parts of an Expression
Term –
Constant –
Like Terms –
Coefficient –
Fill in each column with the appropriate pieces for each expression
Expression:
Coefficients:
Like Terms:
Constants:
6 + 2x + 4x
6, 2, 4
2x, 4x
6
-4x
3m – 2n + n - 4
3x – 5y -3
6xy – 5xy
9m + 2r -2m + r
Lesson 2-3