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10. Solve: 3x² - x - 5 = 0

User Zganger
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1 Answer

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You have the following equation:

3x² - x - 5 = 0

In order to solve the previous equation, use the quadratic formula, given by:


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

where a, b anc c are the coeficients of the polynomial of the equation:

a = 3, b = -1, c = -5

replace the previous values into the quadratic formula:


\begin{gathered} x=\frac{-(-1)\pm\sqrt[]{-(-1)^(2)-4(3)(-5)}}{2(3)} \\ x=\frac{1\pm\sqrt[]{-1+60}}{6} \\ x=\frac{1\pm\sqrt[]{59}}{6} \end{gathered}

Then, you have the following two solutions:

x1 = (1 + √59)/6

x2 = (1 - √59)/6

User Nicholas TJ
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