http://. is this a “ positive 5 ” or “ plus 5 ”? +5 both
TRANSCRIPT
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Is this a “positive 5” or “plus 5”? +5
is the same a s apositive 5 plus 5
BOTH
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HINT: If you don’t see a negative or positive sign in front of a number it is always positive.
5+
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Is this a “negative 7” or “minus 7”?
-7
BOTH
is the same as a negative 7 minus 7
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HINT: The sign in front of the number BELONGS TO THE NUMBER!
–7
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“Simplify” means to combine like terms and complete all operations
2x + 2x + 3x = 7x
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Terms in an expression are like terms if they have identical variable parts.
You can combine terms that are alike.
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To look at combining like terms we
are going to use ALGEBRA TILES!
Algebra Tiles help us to visualize
what each term represents.
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Small Square
Area = 1
Rectangle
x
1
1
1
Area = x
Large Square
x
x
Area = x2
Algebra Tiles
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How much do I have here?
I have 5x + 4
Algebra Tiles
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How much do I have here?
I have x2 + 2x + 6Notice that we write the largest shape first, then the medium size, then the smallest. We write them in order from largest to smallest.
Algebra Tiles
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You can only combine terms that are alike, or terms that have the same variable.
When I combine like terms I have 2x2+ 3x + 6
x2 x x2x x
6
Algebra Tiles
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You are going to get your own set of algebra tiles to use.
Take them out of the bag and put them on your desk. The red should be on the bottom.
Algebra Tiles
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Small Square
Area = 1
Rectangle
x
1
1
1
Area = x
Large Square
x
x
Area = x2
Algebra Tiles
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Small Square
Area = -1
Rectangle
x
1
-1
-1
Area = -x
Large Square
x
-x
Area = -x2
Algebra Tiles
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Show me 3 + x2 with your tiles
Since no terms are alike, we can’t combine anything, so my answer is x2 + 3
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Show me x +3 + 2x with your tiles
We can combine the terms that are alike. So my answer is is 3x + 3
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Show me 3x + 2 + x + 4 with your tiles
We can combine the terms that are alike. So my answer is is 4x + 6
Algebra Tiles
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Try these problems with your algebra tiles. Combine like terms. Give me a thumbs up when you know the answer.
= 6x + 5
= 3x2+ 2x + 4
= 4x2 +3x+2
1) 2x + 4 + 4x + 1
2) 2x2 +2x + 3 + x2 + 1
3) 1 + 3x + 3x2 + 1 + x2
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Like terms can be combined!Like Terms Unlike Terms
7x 3x 7x 3y
5a 4 a 4 3a
6m m 3x 2x
10x
9a
5m
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Combine the following like terms.1) 3x + 5y + 4x
2) 4a + 6 - 3a - 2
7x + 5y
a + 4
Say these!
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Combine the following like terms.
Say these!3) x + 3y + 2x + 4y - z
4) 2 2 25x 4x 3x x 6x
3x + 7y - z
29x 10x
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1) 7m - 2m + 8m
2) -3y + y - 8y
3) 11r - 5r - 9r
4) -3k + 5k + -k + 2k
5) t - 4t + -3t + 2t
6) 11x - 4x + x + -3x
13m
-10y
-3r
3k
-4t
5x
Say these!
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Put your algebra tiles back in your bag and ziplock them.
Pass your tiles forward quickly.
Take Out Your Study Guide!!!
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When I combine like terms I have 2x2+ 3x +6
x2 x x2x x 6
#5 Terms are in expressions or equations, and they are separated by addition or subtraction signs. 6x2 + 3x -
43 terms
Write terms in order from largest shape to smallest.
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Combine Like TermsYou can only combine
terms that are alike, or terms that have the
same variable.
#6
1) 7x - 4y + 2x - y
2) 3m + 10n - 4m + 1
3) 6a - (5a) + 2a + (-3)
4) 4k - (2j) - 6k - j
9x
-m
3a
-2k - 3j
- 5y
+ 10n + 1
- 3
1
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Extra slides
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x2
#Extra
x
x
A = x • x = x2
y2y
yA = y • y = y2
x
1
A = 1 • x = x
x
y
1
A = 1 • y = y
y
xyx
y
A = x • y = xy
11
A = 1
1 1-1
A = -1
-1