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Step 2 of 2 (Step 1, a = 1, b = 7, c = -2)Use the discriminant, b^2 - 4ac, to determine the number of solutions of the given quadratic equation. x^2 + 7x - 2 = 0Then solve the quadratic equation using the formula X = (Formula to use in the pic attached)

Step 2 of 2 (Step 1, a = 1, b = 7, c = -2)Use the discriminant, b^2 - 4ac, to determine-example-1
User Daniel Szalay
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1 Answer

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The equation:


x^2+7x-2=0

has the values a=1, b=7 and c=-2; hence the discriminant is:


7^2-4(1)(-2)=49+8=57

Since the disciminant is positive this means that the equation will have two different solutions.

The solutions can be found using the general formula:


\begin{gathered} x=\frac{-7\pm\sqrt[]{7^2-4(1)(-2)}}{2(1)} \\ x=\frac{-7\pm\sqrt[]{57}}{2} \end{gathered}

therefore the solutions are:


\begin{gathered} x=-(7)/(2)+\frac{\sqrt[]{57}}{2} \\ \text{and} \\ x=-(7)/(2)-\frac{\sqrt[]{57}}{2} \end{gathered}

User Hopobcn
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