Download - Int Math 2 Section 2-4 1011
SECTION 2-4Add and Subtract Variable Expressions
ESSENTIAL QUESTIONS
How are variable expressions simplified?
How are variable expressions evaluated?
Where you’ll see this:
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VOCABULARY1. Terms:
2. Like Terms:
3. Unlike Terms:
4. Simplify:
5. Combining Like Terms:
VOCABULARY1. Terms: The parts of a variable expression that are separated
by addition or subtraction signs
2. Like Terms:
3. Unlike Terms:
4. Simplify:
5. Combining Like Terms:
VOCABULARY1. Terms: The parts of a variable expression that are separated
by addition or subtraction signs
2. Like Terms: Have identical variable parts
3. Unlike Terms:
4. Simplify:
5. Combining Like Terms:
VOCABULARY1. Terms: The parts of a variable expression that are separated
by addition or subtraction signs
2. Like Terms: Have identical variable parts
3. Unlike Terms: Have different variable parts
4. Simplify:
5. Combining Like Terms:
VOCABULARY1. Terms: The parts of a variable expression that are separated
by addition or subtraction signs
2. Like Terms: Have identical variable parts
3. Unlike Terms: Have different variable parts
4. Simplify: Perform as many of the given operations as possible
5. Combining Like Terms:
VOCABULARY1. Terms: The parts of a variable expression that are separated
by addition or subtraction signs
2. Like Terms: Have identical variable parts
3. Unlike Terms: Have different variable parts
4. Simplify: Perform as many of the given operations as possible
5. Combining Like Terms: When you simplify and add or subtract like terms
EXAMPLE 1Add two terms to the list that are like terms.
a. 4x, 18x, -3.7x b. 17h2 , .98h2 , − 15h2
EXAMPLE 1Add two terms to the list that are like terms.
a. 4x, 18x, -3.7x b. 17h2 , .98h2 , − 15h2
Sample: x, 7x, -2x
EXAMPLE 1Add two terms to the list that are like terms.
a. 4x, 18x, -3.7x b. 17h2 , .98h2 , − 15h2
Sample: x, 7x, -2x Sample: h2 , 18h2 , − 4h2
EXAMPLE 2Simplify.
a. 3 x + 8 x b. 2x + 4x2 + (−3x ) + (−10x2 )
c. 7( x + y) + 4( x + y)
EXAMPLE 2Simplify.
a. 3 x + 8 x b. 2x + 4x2 + (−3x ) + (−10x2 )
c. 7( x + y) + 4( x + y)
11 x
EXAMPLE 2Simplify.
a. 3 x + 8 x b. 2x + 4x2 + (−3x ) + (−10x2 )
c. 7( x + y) + 4( x + y)
11 x −6x2 − x
EXAMPLE 2Simplify.
a. 3 x + 8 x b. 2x + 4x2 + (−3x ) + (−10x2 )
c. 7( x + y) + 4( x + y)
11 x −6x2 − x
11( x + y)
EXAMPLE 2Simplify.
a. 3 x + 8 x b. 2x + 4x2 + (−3x ) + (−10x2 )
c. 7( x + y) + 4( x + y)
11 x −6x2 − x
11( x + y)
11x + 11 y
EXAMPLE 3Simplify.
a. .1m − 1.1m b. 7 y + 4x − 7 y − 3x
c. 12x2 + 3 y − 6x2 − 2 y − 6x2
EXAMPLE 3Simplify.
a. .1m − 1.1m b. 7 y + 4x − 7 y − 3x
c. 12x2 + 3 y − 6x2 − 2 y − 6x2
−m
EXAMPLE 3Simplify.
a. .1m − 1.1m b. 7 y + 4x − 7 y − 3x
c. 12x2 + 3 y − 6x2 − 2 y − 6x2
−m x
EXAMPLE 3Simplify.
a. .1m − 1.1m b. 7 y + 4x − 7 y − 3x
c. 12x2 + 3 y − 6x2 − 2 y − 6x2
−m x
y
SOME IMPORTANT IDEAS
SOME IMPORTANT IDEAS
Compare variable parts
SOME IMPORTANT IDEAS
Compare variable parts
Work alphabetically, then highest power
SOME IMPORTANT IDEAS
Compare variable parts
Work alphabetically, then highest power
Simplify first, then evaluate
EXAMPLE 4Evaluate each expression when x = 2 and y = -3.
a. 6x2 + 3x2 b. 3x2 − y − x2
EXAMPLE 4Evaluate each expression when x = 2 and y = -3.
a. 6x2 + 3x2 b. 3x2 − y − x2
9x2
EXAMPLE 4Evaluate each expression when x = 2 and y = -3.
a. 6x2 + 3x2 b. 3x2 − y − x2
9x2
9(2)2
EXAMPLE 4Evaluate each expression when x = 2 and y = -3.
a. 6x2 + 3x2 b. 3x2 − y − x2
9x2
9(2)2
9(4)
EXAMPLE 4Evaluate each expression when x = 2 and y = -3.
a. 6x2 + 3x2 b. 3x2 − y − x2
9x2
9(2)2
9(4)
36
EXAMPLE 4Evaluate each expression when x = 2 and y = -3.
a. 6x2 + 3x2 b. 3x2 − y − x2
9x2
9(2)2
9(4)
36
2x2 − y
EXAMPLE 4Evaluate each expression when x = 2 and y = -3.
a. 6x2 + 3x2 b. 3x2 − y − x2
9x2
9(2)2
9(4)
36
2x2 − y
2(2)2 − (−3)
EXAMPLE 4Evaluate each expression when x = 2 and y = -3.
a. 6x2 + 3x2 b. 3x2 − y − x2
9x2
9(2)2
9(4)
36
2x2 − y
2(2)2 − (−3)
8 + 3
EXAMPLE 4Evaluate each expression when x = 2 and y = -3.
a. 6x2 + 3x2 b. 3x2 − y − x2
9x2
9(2)2
9(4)
36
2x2 − y
2(2)2 − (−3)
8 + 3
11
EXAMPLE 4
c. x2 − 4 y − 2x2 + y
Evaluate each expression when x = 2 and y = -3.
EXAMPLE 4
c. x2 − 4 y − 2x2 + y
−x2 − 3 y
Evaluate each expression when x = 2 and y = -3.
EXAMPLE 4
c. x2 − 4 y − 2x2 + y
−x2 − 3 y
−(2)2 − 3(−3)
Evaluate each expression when x = 2 and y = -3.
EXAMPLE 4
c. x2 − 4 y − 2x2 + y
−x2 − 3 y
−(2)2 − 3(−3)
−4 + 9
Evaluate each expression when x = 2 and y = -3.
EXAMPLE 4
c. x2 − 4 y − 2x2 + y
−x2 − 3 y
−(2)2 − 3(−3)
−4 + 9
5
Evaluate each expression when x = 2 and y = -3.
PROBLEM SET
PROBLEM SET
p. 68 #1-43 odd, skip #13
“Use what talents you possess: the woods would be very silent if no birds sang except those that sang best.” - Henry Van
Dyke