Use the Commutative, Associative, andDistributive Properties to simplify expressions.
Combine like terms.
Objectives
Holt Algebra 1
1-7
Simplifying Expressions
Holt Algebra 1
1-7
Simplifying Expressions
Check It Out! Example 1c
Simplify.
28
Use the Commutative Property.
Use the Associative Propertyto make groups of compatiblenumbers.
1
2
•
7 • 8
1
2
•
8•7
(
)
1
2
•
8
7
4
•
7
Holt Algebra 1
1-7
Simplifying Expressions
The Distributive Property is used with Addition toSimplify Expressions.
The Distributive Property also works withsubtraction because subtraction is the same asadding the opposite.
Holt Algebra 1
1-7
Simplifying Expressions
The terms of an expression are the parts to beadded or subtracted. Like terms are terms thatcontain the same variables raised to the samepowers. Constants are also like terms.
4x –3x + 2
Like terms
Constant
Holt Algebra 1
1-7
Simplifying Expressions
A coefficientis a number multiplied by avariable. Like terms can have differentcoefficients. A variable written without acoefficient has a coefficient of 1.
1x2 + 3x
Coefficients
Holt Algebra 1
1-7
Simplifying Expressions
Using the Distributive Property can help youcombine like terms. You can factor out thecommon factors to simplify the expression.
7x2 – 4x2 = (7 – 4)x2
= (3)x2
= 3x2
Factor out x2 from both terms.
Perform operations inparenthesis.
Notice that you can combine like terms byadding or subtracting the coefficients andkeeping the variables and exponents the same.
Holt Algebra 1
1-7
Simplifying Expressions
Example 3A: Combining Like Terms
Simplify the expression by combining liketerms.
72p – 25p
72p –25p
47p
72p and 25p are like terms.
Subtract the coefficients.
Holt Algebra 1
1-7
Simplifying Expressions
Example 3C: Combining Like Terms
Simplify the expression by combining liketerms.
0.5m + 2.5n
0.5m + 2.5n
0.5m + 2.5n
0.5m and 2.5n are not like terms.
Do not combine the terms.
Holt Algebra 1
1-7
Simplifying Expressions
Check It Out! Example 3
Simplify by combining like terms.
3a. 16p + 84p
16p + 84p
100p
1
6
p
+
8
4
p
a
r
e
l
i
k
e
t
e
r
m
s
.
A
d
d
t
h
e
c
o
e
f
f
i
c
i
e
n
t
s
.
3b. –20t – 8.5t2
–20t – 8.5t2
20t and 8.5t2 are not like terms.
–20t – 8.5t2
Do not combine the terms.
3m2 + m3
3m2 and m3are not like terms.
3c. 3m2 + m3
Do not combine the terms.
3m2 + m3
Holt Algebra 1
1-7
Simplifying Expressions
Example 4: Simplifying Algebraic Expressions
Simplify 14x + 4(2 + x). Justify each step.
14x + 4(2) + 4(x)
Distributive Property
Multiply.
Commutative Property
Associative Property
Combine like terms.
14x + 8 + 4x
(14x + 4x) + 8
14x + 4x + 8
18x + 8
14x + 4(2 + x)
1.
2.
3.
4.
5.
6.
Procedure
Justification
Holt Algebra 1
1-7
Simplifying Expressions
6(x)–6(4) + 9
Distributive Property
Multiply.
Combine like terms.
6x – 24 + 9
6x – 15
6(x –4) + 9
1.
2.
3.
4.
Procedure
Justification
Check It Out! Example 4a
Simplify 6(x –4) + 9.Justify each step.
Holt Algebra 1
1-7
Simplifying Expressions
–12x – 5x + x + 3a
Commutative Property
Combine like terms.
–16x + 3a
–12x – 5x + 3a + x
1.
2.
3.
Procedure
Justification
Check It Out! Example 4b
Simplify −12x – 5x + 3a + x.Justify each step.
Holt Algebra 1
1-7
Simplifying Expressions
Lesson Quiz: Part I
Simplify each expression.
1. 165 +27 + 3 + 5
2.
Write each product using the DistributiveProperty. Then simplify.
3. 5($1.99)
4. 6(13)
200
8
5($2) – 5($0.01) = $9.95
6(10) + 6(3) = 78
Holt Algebra 1
1-7
Simplifying Expressions
Lesson Quiz: Part II
Simplify each expression by combining liketerms. Justify each step with an operation orproperty.