-x2+3x+8=0

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Solution for -x2+3x+8=0 equation:



-x2+3x+8=0
We add all the numbers together, and all the variables
-1x^2+3x+8=0
a = -1; b = 3; c = +8;
Δ = b2-4ac
Δ = 32-4·(-1)·8
Δ = 41
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-\sqrt{41}}{2*-1}=\frac{-3-\sqrt{41}}{-2} $
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+\sqrt{41}}{2*-1}=\frac{-3+\sqrt{41}}{-2} $

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