Name
LESSON
8-2
Date
Class
Practice A
Multiplying and Dividing Rational Expressions
Answer each question.
1. What could make a rational expression undefined?
Possible answer: If the denominator is 0, then the expression is undefined
because division by 0 is impossible.
2. What value of x gives a denominator equal to 0 for the
4?
expression x_____
x3
x⫽3
Simplify. Identify any x-values for which the expression is undefined.
2
x_______
3x
5x
4.
3. ___
3
x3
x
x⫹3
5;x(0
___
2
______; x ( c
2
x
x
7
______
6. 2x
x3
12
_______
5. 4x
6x 18
2x
⫹ 7; x ( 0
______
x⫹3
2 ; x ⫽ ⫺3
__
3
Complete. Assume that all expressions are defined.
3x
3x • __
2 _____
7. ___
y
2y
y2
4
3y 2
2x 5 • ____
2x
8. ____
_____
4
x
9y
3y 2
x⫹8
8x • ________
x
_______
10. x________
3
2
x
x 4x
x⫹4
4
2 • _____________
4x 4
9. x_____
_______
x 1 x 2 x 2 x⫺2
3
2
2
2
y
3y
2x • ___
2x ___
2x ___
_____
11. ___
2
2
3y
3y
3y
2x
x
2x ⫹ 4
x 1 x 2 15
1•2
________
________
12. x_____
x_____
_________
x2
x 2 5 x 1 2 x 2 5x ⫺ 10
1
4y
2y
2y
4 _____
13. _____ _____ _____ • x_____
2
x4
x4
x4
4y
2y
2
Solve.
2
2x 8
________
14. 2x
x1
9x 9 1
15. _______
x3 x2
x⫽4
x⫽3
2
15x 10
_________
16. 5x
x3
2
3x 2 1
17. x__________
2x 2 4
x⫽2
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
a207c08-2_pr.indd 11
x⫽1
11
Holt Algebra 2
12/26/05 6:46:16 AM
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