Exercise 1 Page 667

We want to simplify the given rational expression. We will start by factoring the expression as much as we can. Then, we will cancel out any common factors.

3x+9/x+3

FactorOut

Factor out 3

3(x+3)/x+3

CancelCommonFac

Cancel out common factors

3(x+3)/x+3

SimpQuot

Simplify quotient

3/1

DivByOne

a/1=a

We simplified the given expression. Finally, we will identify the restrictions on the variable from the denominator of the simplified expression and from any other denominator used. Since our final expression is not a fraction, we need to look at the expression before canceling out common factors.

Denominator	Restrictions on the Denominator	Restrictions on the Variable
x+3	x+3≠ 0	x≠ - 3

We found one excluded value of the variable x. x≠ - 3

Subchapter links

Lesson Check p.667

Practice and Problem-Solving Exercises p.667-669