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2x^2 +6x=-3 can you compute this?

1 Answer

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The general formula for a quadratic equation is ax² + bx + c = 0.

To solve


2x^2+6x=-3

You can follow the steps.

Step 01: Write the equation in the general formula.

To do it, add 3 to each side of the equation.


\begin{gathered} 2x^2+6x+3=-3+3 \\ 2x^2+6x+3=0 \end{gathered}

Step 02: Use the Bhaskara formula to find the roots.

The Bhaskara formula is:


x=\frac{-b\pm\sqrt[]{\Delta}}{2\cdot a},\Delta=b^2-4\cdot a\cdot c

In this question,

a = 2

b = 6

c = 2

So, substituting the values:


\begin{gathered} \Delta=b^2-4\cdot a\cdot c \\ \Delta=6^2-4\cdot2\cdot3 \\ \Delta=36-24 \\ \Delta=12 \\ \\ x=\frac{-6\pm\sqrt[]{12}}{2\cdot2} \\ x=\frac{-6\pm\sqrt[]{2\cdot2\cdot3}}{4} \\ x=\frac{-6\pm2\cdot\sqrt[]{3}}{4} \\ x_1=\frac{-6+2\sqrt[]{3}}{4}=\frac{-3+\sqrt[]{3}}{2} \\ x_2=\frac{-6-2\sqrt[]{3}}{4}=\frac{-3-\sqrt[]{3}}{2} \end{gathered}

Answer:

Exact form:


x=\frac{-3-\sqrt[]{3}}{2},\frac{-3+\sqrt[]{3}}{2}

Decimal form:


x=-2.37,\text{ -0.63}

User Ivan Coronado
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