College Algebra (10th Edition)

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

Chapter 1 - Section 1.4 - Radical Equations; Equations Quadratic in Form; Factorable Equations - 1.4 Assess Your Understanding: 85

Answer

$x=\frac{1}{2}$ or $x=2$ or $x=-2$

Work Step by Step

We solve by factoring with grouping: $2x^{3}+4=x^{2}+8x$ $2x^{3}+4-x^{2}-8x=0$ $2x^{3}-x^{2}-8x+4=0$ $x^{2}(2x-1)-4(2x-1)=0$ $(2x-1)(x^{2}-4)=0$ $(2x-1)(x-2)(x+2)=0$ $2x-1=0$ or $x-2=0$ or $x+2=0$ $2x=1$ or $x=2$ or $x=-2$ $x=\frac{1}{2}$ or $x=2$ or $x=-2$
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.