Combining Like Terms

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Combining Like Terms

• Students will identify like terms and combine
  like terms to solve problems.

2
Combine Like Fruits
2 bananas
3 apples
3 bananas
4 apples
4 3 apples
3 2 bananas
5 bananas
7 apples
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Only combine terms that are the same!!

• Whats the SAME or Like Terms mean?
• The variables (letters) MUST be the same with the
  SAME POWERS.
• You can also combine numbers that have no
  variables.

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Examples

• Which terms are the same or LIKE TERMS?
• 5x, 8y, 9z, 10, x2, 12x, 14z, 7, 3x2

5x and
?
12x
10 and
?
7
x2 and
?
3x2
8y and
NOTHING!
?
9z and
?
14z
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Combining Terms

• To combine Like Terms, add or subtract the
  coefficients (numbers in front of the variables)
  The variable stays the same.

Example 5x 9x
THINK 5 9 14 and bring down the x.
14x
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Lets try it!

• 4x 9x
• 13x

-7y 9y 2y
-8y (-4y) -12y
4x 8y 10x 14x
5 8x 7y 10 8x
8y
7y
15
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More Problems

• 4x 5y 2x 3y
• 2x
• 5(x y) 2(x y)
• 5x 5y 2x 2y
• 7x
• 3. 3 5x 4y 2y 8x
• 3

8y
Use the distributive property first.
7y
3x
2y
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Problems Cont.

• 4. (-13) (-2y) (-7) 4y
• -20
• 5. 8(2x 3y) 4(y 3x)
• 16x
• 4x

6y
24y
4y
12x
20y
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Summary

• Combine LIKE TERMS only if they have exactly the
  same letters with the same powers.
• Combine Like Terms by adding or subtracting the
  coefficients (numbers)
• Constants (terms without variables) can also be
  combined by adding or subtracting.

END