x^2+2.8x+1.6=0

Solution for x^2+2.8x+1.6=0 equation:

x^2+2.8x+1.6=0

a = 1; b = 2.8; c = +1.6;
Δ = b2-4ac
Δ = 2.82-4·1·1.6
Δ = 1.44
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{1.44}}{2*1}=\frac{-2.8-\sqrt{1.44}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2.8)+\sqrt{1.44}}{2*1}=\frac{-2.8+\sqrt{1.44}}{2}
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