x^2-2.8x-9.6=0

Solution for x^2-2.8x-9.6=0 equation:

x^2-2.8x-9.6=0

a = 1; b = -2.8; c = -9.6;
Δ = b2-4ac
Δ = -2.82-4·1·(-9.6)
Δ = 46.24
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{-(-2.8)-\sqrt{46.24}}{2*1}=\frac{2.8-\sqrt{46.24}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2.8)+\sqrt{46.24}}{2*1}=\frac{2.8+\sqrt{46.24}}{2}
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