x^2-10.5x+5=0

Solution for x^2-10.5x+5=0 equation:

x^2-10.5x+5=0

a = 1; b = -10.5; c = +5;
Δ = b2-4ac
Δ = -10.52-4·1·5
Δ = 90.25
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{-(-10.5)-\sqrt{90.25}}{2*1}=\frac{10.5-\sqrt{90.25}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-10.5)+\sqrt{90.25}}{2*1}=\frac{10.5+\sqrt{90.25}}{2}
$