1. Simplifying Algebraic Expressions 6.ee.3
Combining Like Terms

2. "I can simplify algebraic expressions by combining like terms."
Learning Targets
By the end of class today, you should be able to say:
"I can simplify algebraic expressions by combining like terms."
In this presentation, you will learn about:
the parts of an algebraic expression
what "like terms" are
how to simplify algebraic expressions by combining like terms

3. Algebraic Expressions: A Review
Let's review what we've learned so far about algebraic expressions.
An algebraic expression is a mathematical phrase that uses numbers, variables, and operation symbols.
 2x + 7 is an example of an algebraic expression
A variable is a symbol that stands for one or more numbers.
x, y, and n are examples of variables

4. Algebraic Expressions: A Closer Look
An algebraic expression can be broken into different parts, including terms, variables, coefficients, and constants.

5. An Algebraic Expression Dissected
5x + 3y -8

6. An Algebraic Expression Dissected
5x + 3y - 8
terms
(numbers, variables, or the product of a number and a variable)

7. An Algebraic Expression Dissected
5x + 3y - 8
coefficients
(numerical factors of a term, or the number before a variable)

8. An Algebraic Expression Dissected
5x + 3y - 8
variables
(symbols that represent numbers that are unknown or can change)

9. An Algebraic Expression Dissected
5x + 3y - 8
constant
(a term that has no variable, or a number by itself)

10. Make it Simple!
To simplify an algebraic expression means to make it simpler.
In other words, rewrite the expression in the most compact way, without changing the value of the expression.  It's like organizing the expression and making it neater!

11. Like Terms 3x, -2x 3x, 3y -2, 5 -2, 5x 9n2, 3n2 9n2, 2n 100, 1
Like terms have exactly the same variable factors
Like or Not Like Terms
LIKE TERMS
3x, -2x
-2, 5
9n2, 3n2
100, 1
4n, 5n
3xy, 4yx 
NOT LIKE TERMS
3x, 3y
-2, 5x
9n2, 2n
2a2b, 3ab2

12. Simplifying by Combining Like Terms
Consider the following algebraic expression:
3a b - 6a b

13. Simplifying by Combining Like Terms
To add the like terms, simply add the coefficients.
3a b - 6a b
-3a
+ 3b
+ 3

14. Now You Try It! (MATH 8) 10h + 12g + h2 + 3gh2 1) 4a + 7 + 2a 6a + 7
Simplify the following expressions by combining like terms.
1)  4a a
  a + 7
2)   -4x x x2
-7x -5 +2x2
  3)   12h - 4g +h2 +16g – 2h +3gh2
10h + 12g + h2 + 3gh2