Chapter 8 Summary and Review 697Variables and/or numbers can be combined
with the operations of addition, subtraction,
multiplication, and division to create algebraic
expressions.
We often refer to algebraic expressionsas
simply expressions.
Expressions:8 a(b3)12 x
5
5 y 7A termis a product or quotient of numbers
and/or variables. A single number or variable
is also a term. A term such as 4, that consists of
a single number, is called a constant term.
Terms: 4, y,6r,–w^3 , 3.7x^5 , –15ab^23
n,
Addition symbols separate expressions into
parts called terms.
The numerical factor of a term is called the
coefficientof the term.
Since can be written as , it has three
terms.6 a^2 a 5 6 a^2 a(5)It is important to be able to distinguish
between the terms of an expressionand the
factors of a term.
x+ 6 6 xxis a term. xis a factor. Key wordsand key phrasescan be translated
into algebraic expressions.
5 more than can be expressed as.
25 less than twice can be expressed as.One-half of the cost ccan be expressed as.1
2
cy 2 y 25x x 5Toevaluate algebraic expressions,we
substitute the values of its variables and apply
the rules for the order of operations.
Evaluate for and.Substitute 2 for xand 3 fory.In the numerator, evaluate the exponential
expressions. In the denominator, add.In the numerator, subtract. 5 Do the division.5
1
4 9
1
x^2 y^2
x y22 ( 3 )^2
2 ( 3 )
x 2 y 3x^2 y^2
xyTerm Coefficient
6
a 1
5 56 a^2