Elementary Algebra

Published by Cengage Learning
ISBN 10: 1285194055
ISBN 13: 978-1-28519-405-9

Chapter 10 - Quadratic Equations - 10.3 - Quadratic Formula - Problem Set 10.3 - Page 453: 2

Answer

{$-4,1$}

Work Step by Step

Step 1: Comparing $x^{2}+3x-4=0$ to the standard form of a quadratic equation, $ax^{2}+bx+c=0$, we obtain: $a=1$, $b=3$ and $c=-4$ Step 2: The quadratic formula is: $x=\frac{-b \pm \sqrt {b^{2}-4ac}}{2a}$ Step 3: Substituting the values of a,b, and c in the formula, we obtain: $x=\frac{-(3) \pm \sqrt {(3)^{2}-4(1)(-4)}}{2(1)}$ Step 4: $x=\frac{-3 \pm \sqrt {9+16}}{2}$ Step 5: $x=\frac{-3 \pm \sqrt {25}}{2}$ Step 6: $x=\frac{-3 \pm 5}{2}$ Step 7: $x=\frac{-3+5}{2}$ or $x=\frac{-3-5}{2}$ Step 8: $x=\frac{2}{2}$ or $x=\frac{-8}{2}$ Step 9: $x=1$ or $x=-4$ Step 10: Therefore, the solution set is {$-4,1$}.
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.