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8x^ +7x + 1 = 0Round your answer to the nearest hundredth.

User Unfrev
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1 Answer

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Quadratic Equations

The general form of a quadratic equation is:


ax^2+bx+c=0

Where a, b, and c are constants.

We can solve the quadratic equation by using the following formula:


x=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a}

The equation:


8x^2+7x+1=0

Has the coefficients a = 8, b = 7, c = 1. Substituting:


x=\frac{-7\pm\sqrt[]{7^2-4\cdot8\cdot1}}{2\cdot8}

Operating:


\begin{gathered} x=\frac{-7\pm\sqrt[]{49-32}}{16} \\ x=\frac{-7\pm\sqrt[]{17}}{16} \end{gathered}

There are two real solutions:


\begin{gathered} x_1=\frac{-7+\sqrt[]{17}}{16} \\ x_2=\frac{-7-\sqrt[]{17}}{16} \end{gathered}

Calculating:

x1 = -0.18

x2 = -0.70

User Andrew Morton
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