-0,15x^2+38,25x+506,25=0

Solution for -0,15x^2+38,25x+506,25=0 equation:

-0.15x^2+38.25x+506.25=0

a = -0.15; b = 38.25; c = +506.25;
Δ = b2-4ac
Δ = 38.252-4·(-0.15)·506.25
Δ = 1766.8125
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{-(38.25)-\sqrt{1766.8125}}{2*-0.15}=\frac{-38.25-\sqrt{1766.8125}}{-0.3}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(38.25)+\sqrt{1766.8125}}{2*-0.15}=\frac{-38.25+\sqrt{1766.8125}}{-0.3}
$