Algebra 1

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

Chapter 9 - Quadratic Functions and Equations - 9-5 Completing the Square - Practice and Problem-Solving Exercises - Page 564: 13



Work Step by Step

$g^2+7g=144$ Compare it with the standard form of quadratic equation $ax^2+bx+c$, we have $a=1, b=7$ Therefore, $b^2=4ac$ $\implies$ $c=\dfrac{b^2}{4a}$ Thus, $c=\dfrac{b^2}{4a}=\dfrac{(7)^2}{4}=\frac{49}{4}$ To complete the square, add $\frac{49}{4}$ on both sides. $g^2+7g+\frac{49}{4}=144+\frac{49}{4}$ $\implies (g+\frac{7}{2})^2=\frac{625}{4}$ $\implies (g+\frac{7}{2})=\frac{625}{4}$ and $\implies (g+\frac{7}{2})=-\frac{625}{4}$ or, $g=9,-16$
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.