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It’s asking me to use the quadratic formula to solve the roots in the following equation which is in the picture

It’s asking me to use the quadratic formula to solve the roots in the following equation-example-1
User JonCav
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1 Answer

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28 votes

Solve the equation:


4x^2+5x+2=2x^2+7x-1

We need to take all terms of the equation to the left side. We do that by subtracting each one of them from both sides of the equation as follows:


4x^2+5x+2-2x^2-7x+1=0

Collecting like terms:


2x^2-2x+3=0

Identify the coefficients: a = 2, b = -2, c = 3. And apply the quadratic formula:


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

Substituting:


x=(-(-2)\pm√((-2)^2-4(2)(3)))/(2(2))

Operating:


\begin{gathered} x=(2\pm√(4-24))/(4) \\ \\ x=(2\pm√(-20))/(4) \end{gathered}

The solutions to the equation are complex because the square root of a negative number is imaginary:


x=(2\pm√(20)i)/(4)

Since 20 = 4*5, this expression can be simplified:


\begin{gathered} x=(2\pm2√(5)i)/(4) \\ \\ x=(1\pm√(5)\imaginaryI)/(2) \end{gathered}

Finally, separating the real and imaginary parts:


x=(1)/(2)\pm(√(5))/(2)i

User Talles
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