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Quadratic Formula Calculator

Get detailed solutions to your math problems with our Quadratic Formula step-by-step calculator. Practice your math skills and learn step by step with our math solver. Check out all of our online calculators here.

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1

Solved example of quadratic formula

$x^2+6x+8=0$
2

To find the roots of a polynomial of the form $ax^2+bx+c$ we use the quadratic formula, where in this case $a=1$, $b=6$ and $c=8$. Then substitute the values of the coefficients of the equation in the quadratic formula: $\displaystyle x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$

$x=\frac{-6\pm 2}{2}$
3

To obtain the two solutions, divide the equation in two equations, one when $\pm$ is positive ($+$), and another when $\pm$ is negative ($-$)

$x=\frac{-6+2}{2},\:x=\frac{-6-2}{2}$

4

Subtract the values $2$ and $-6$

$x=\frac{-4}{2},\:x=\frac{-6-2}{2}$
5

Subtract the values $-6$ and $-2$

$x=\frac{-4}{2},\:x=\frac{-8}{2}$
6

Divide $-4$ by $2$

$x=-2,\:x=\frac{-8}{2}$
7

Divide $-8$ by $2$

$x=-2,\:x=-4$

Final Answer

$x=-2,\:x=-4$

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