College Algebra (10th Edition)

Published by Pearson
ISBN 10: 0321979478
ISBN 13: 978-0-32197-947-6

Chapter R - Section R.7 - Rational Expressions - R.7 Assess Your Understanding - Page 71: 28


$\displaystyle \frac{3(x-4)}{5x}$

Work Step by Step

$...=\displaystyle \frac{12x}{5x+20}\div\frac{4x^{2}}{x^{2}-16}=\frac{12x}{5x+20}\cdot\frac{x^{2}-16}{4x^{2}}$ Factoring, $12=4\cdot 3$ $ x^{2}-16=(x+4)(x-4)\quad$ (a difference of squares) $5x+20=5(x+4)$ $x^{2}=x\cdot x$ ... = $\displaystyle \frac{4\cdot 3\cdot x\cdot(x+4)(x-4)}{5(x+4)\cdot 4\cdot x\cdot x}$ ... cancel the following from both sides of the fraction line: $4,\ x$, $(x+4)$ ... = $\displaystyle \frac{3(x-4)}{5x}$
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.