1. Combining Like Terms

2. 3x-4=9 What is a term? A part of an equation or expression
Coefficient- A number used to multiply a variable
Constant- A number on its own
3x-4=9
Coefficient
Constants
Term
Term
Term

3. 7y-2+9x=13 Example Terms: Coefficients: Constants: Variables: 7y , -2
, 13
, 9x 7
, 9 -2
, 13 Y
, X

4. What EXACTLY does the same or “Like” mean?
Terms with the same variable or variables and raised to the same power
Same: 5x and 12x
Same: 10 and 7
Same: 9z and 14z
Same: 8y
5x, 8y, 9z, 10, 12x, 14z, 7

5. Document camera
I couldn’t find a very fun video but I did really like the way the woman explained the concept in these videos so I think I’ll just use the document camera to do a shorter version of what she did in these following videos
expressions/simplifying-expressions-examples/like-terms-definition
expressions/simplifying-expressions-examples/add-like-terms-example

6. What is Combining like terms
If numbers have a variable, then you can combine only ones that have the same variable
Also if numbers don’t have variables they can only be combined with other numbers that don’t have variables
Like terms could be combined by adding their coefficients

7. How To Combine like Terms
First, change our operators to addition by using keep- change-change
Second, Reorder the expression so like terms are next to each other
Finally, combine like terms by adding their coefficients (simplify)

8. + – + + +( – ) + + Combine like terms–
( – ) +
By combining apples with apples and oranges with oranges, you get... +
Emphasize equivalent equations
3 apples + 2 oranges +(- 2) apples + 2 oranges
coefficients
1 apple
oranges

9. 4 + 2 -2 -1 =4 +2 +(-2 )+(-1 ) = + + + = + =2 +1 Example Good Movies
= (-2 )+(-1 ) =
No notes
= =

10. Remember: adding the opposite cancels out so
Example: Simplify 2x - 3y + 5x + 3y + 12
Change everything to addition
2x + (-3y) + 5x + 3y + 12
Reorder your terms
2x+5x+(-3y)+(3y)+12
Find the like terms
2x +5x +(-3y) +3y +12
Combine like terms
7x +12
Remember: adding the opposite cancels out so
(-3x)+(3x)=0

11. Simplify: 4x2-13y+4x+12x2-3x+3 4x2 +(-13y) +4x +12x2 +(-3x) +3
Change all operations to addition using keep-change-change
4x2 +(-13y) +4x +12x2 +(-3x) +3
Reorder the terms
Before bringing up the first step ask the students where we will need to apply kcc
This slide will allow me to emphasize how like terms also must include variable to the same power
Have the students do this problem on their whiteboards
4x2 +12x2+ 4x +(-3x)+(-13y)+3
Combine like terms (simplify)
16x2 + x + (-13y) + 3

12. Combine like terms A. 14a – 5a 14a +(-5a) 9a
Change any subtraction to addition
14a
+(-5a)
Reorder Terms
For the first example I can also pose the question: what if I had 14a and just -5, would I have like terms?
If I get asked why we have to apply keep change change to the first example I’ll let students know that examples are going to get more complicated so we want you to get in the habit of applying this process while the problems are easier
First problem in their notes, second problem on the white boards
Identify like terms. 9a
Combine coefficients: 14 – 5 = 9

13. Combine like terms B. 7y + 8 – 3y – 1 + y 7y +8 +(-3y) +(-1) +y
Change any subtraction to addition
B. 7y + 8 – 3y – 1 + y
Reorder Terms
7y +8 +(-3y) +(-1) +y
Identify like terms ; the coefficient of y is 1, because 1y = y.
7y +(-3y)+y
+8 +(-1)
Combine coefficients:
7 – = 5 and 8 – 1 = 7
5y + 7

14. Combine like terms (on the boards).
Change any subtraction to addition
C. 4q – q
Reorder Terms
4q +(-1q)
Identify like terms ; the coefficient of q is 1, because 1q = q. 3q
Combine coefficients:
4 +(-1) = 3.

15. Combine like terms (on the boards).
D. 5c + 8 – 5c – 2
Change any subtraction to addition
5c + 8 +(-5c) +(–2)
Reorder Terms
5c +(-5c) +8 +(–2)
Identify like terms ; the coefficient of q is. 6
Combine coefficients:
4 +(-1) = 3.

16. Combine like terms (on the boards).
F. 5m2 – 7m – 8 + 4
Change any subtraction to addition
5m2 +(-7m) + (-8) + 4
Reorder Terms
5m2 +(-7m) +(-8) +4
Identify like terms ; the coefficient of q is.
Combine coefficients:
4 +(-1) = 3.
5m2 – 7m – 4

17. Combine like terms (in your notes).
E. 4m + 9n – 2
4m +9n +(-2)
Change any subtraction to addition
Reorder Terms
4m + 9n – 2
Identify like terms ; the coefficient of q is.
Combine coefficients.
No like terms.