x^2-2.8x+1.3=0

Solution for x^2-2.8x+1.3=0 equation:

x^2-2.8x+1.3=0

a = 1; b = -2.8; c = +1.3;
Δ = b2-4ac
Δ = -2.82-4·1·1.3
Δ = 2.64
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{2.64}}{2*1}=\frac{2.8-\sqrt{2.64}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2.8)+\sqrt{2.64}}{2*1}=\frac{2.8+\sqrt{2.64}}{2}
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