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Find the zeros by using the quadratic formula and tell whether the solutions are real or imaginary. F(x)=x^2+12x–5

User Michael Harper
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1 Answer

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13 votes

To find the values of x such that f(x)=0, substitute that condition into the equation:


x^2+12x-5=0

Use the quadratic formula with a=1, b=12 and c=-5.


\begin{gathered} x=\frac{-(12)\pm\sqrt[]{(12)^2-4(1)(-5)}}{2(1)} \\ \Rightarrow \\ x=\frac{-12\pm\sqrt[]{144+20}}{2} \\ \Rightarrow \\ x=\frac{-12\pm\sqrt[]{164}}{2} \end{gathered}

Since the number inside the square root is positive, then the solutions are real numbers.

User Reexmonkey
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