-0.125x^2+4.7x+10.5=0

Solution for -0.125x^2+4.7x+10.5=0 equation:

-0.125x^2+4.7x+10.5=0

a = -0.125; b = 4.7; c = +10.5;
Δ = b2-4ac
Δ = 4.72-4·(-0.125)·10.5
Δ = 27.34
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{-(4.7)-\sqrt{27.34}}{2*-0.125}=\frac{-4.7-\sqrt{27.34}}{-0.25}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4.7)+\sqrt{27.34}}{2*-0.125}=\frac{-4.7+\sqrt{27.34}}{-0.25}
$