Use the quadratic formula to solve the quadratic equation.
-$x ^ { 2 } + 2 x = 80$
A)x = -10, 1
B)x = 10, 8
C)x = -10, 8
D)x = 10, -8

Name: Use the quadratic formula to solve the quadratic equation. -$x ^ { 2 } + 2 x = 80$ A)x = -10, 1 B)x = 10, 8 C)x = -10, 8 D)x = 10, -8
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Quizplus · Accepted Answer

First, rewrite the equation in standard form: $x^2 + 2x - 80 = 0$. Then, apply the quadratic formula $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$ with $a = 1$, $b = 2$, and $c = -80$. Solving gives $x = -10$ and $x = 8$.

Use the Quadratic Formula to Solve the Quadratic Equation x2+2x=80x ^ { 2 } + 2 x = 80x2+2x=80

Use the Quadratic Formula to Solve the Quadratic Equation $x ^ { 2 } + 2 x = 80$