Thinking Mathematically (6th Edition)

Published by Pearson
ISBN 10: 0321867327
ISBN 13: 978-0-32186-732-2

Chapter 6 - Algebra: Equations and Inequalities - 6.5 Quadratic Equations - Exercise Set 6.5 - Page 400: 63

Answer

the solution set is\[\left\{ -\frac{2}{3},\frac{3}{2} \right\}\].

Work Step by Step

The given equation can be written as \[6{{x}^{2}}-5x-6=0\]. Compare the given equation with the equation\[a{{x}^{2}}+bx+c=0\]. Here,\[a=6,\,\,b=-5,\text{ and }c=-6\]. Now put these values in the quadratic formula: \[x=\frac{-b\pm \sqrt{{{b}^{2}}-4ac}}{2a}\] That is, \[\begin{align} & x=\frac{5\pm \sqrt{{{\left( -5 \right)}^{2}}-4\times 6\times \left( -6 \right)}}{2\times 6} \\ & =\frac{5\pm \sqrt{25+144}}{12} \\ & =\frac{5\pm \sqrt{169}}{12} \\ & =\frac{5\pm 13}{12} \end{align}\] Further simplify it to get, \[\begin{align} & x=\frac{5\pm 13}{12} \\ & =\frac{5+13}{12},\frac{5-13}{12} \\ & =\frac{18}{12},-\frac{8}{12} \\ & =\frac{3}{2},-\frac{2}{3} \end{align}\] Hence, the solution set is\[\left\{ -\frac{2}{3},\frac{3}{2} \right\}\].
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.