Algebra 1

Published by Prentice Hall
ISBN 10: 0133500403
ISBN 13: 978-0-13350-040-0

Chapter 11 - Rational Expressions and Functions - Mid-Chapter Quiz - Page 678: 5


$-\dfrac{(x+3)}{(x+4)}$; $x \ne 3$

Work Step by Step

Given: $\dfrac{9-x^2}{x^2+x-12}$ Need to find the common factors of the given expression. $\dfrac{9-x^2}{x^2+x-12}=\dfrac{(3^2-x^2)}{(x+4)(x-3)}$ $=\dfrac{(3-x)(3+x)}{(x+4)(x-3)}$ $=-\dfrac{(x-3)(3+x)}{(x+4)(x-3)}$ $=-\dfrac{(x+3)}{(x+4)}$ If we put $x=3$ then numerator becomes zero, which cannot be possible. After simplification, we get $=-\dfrac{(x+3)}{(x+4)}$; $x \ne 3$
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.