Basic Mathematics for College Students

(Nandana) #1
Chapter 8 Summary and Review 697

Variables 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 7

A 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^2

3


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 x

xis 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


c

y 2 y 25

x x 5

Toevaluate 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 y




22 ( 3 )^2


2 ( 3 )


x 2 y 3

x^2 y^2
xy

Term Coefficient
6
a 1
 5  5

6 a^2
Free download pdf