-4.9x^2+5.2x+125=0

Solution for -4.9x^2+5.2x+125=0 equation:

-4.9x^2+5.2x+125=0

a = -4.9; b = 5.2; c = +125;
Δ = b2-4ac
Δ = 5.22-4·(-4.9)·125
Δ = 2477.04
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{-(5.2)-\sqrt{2477.04}}{2*-4.9}=\frac{-5.2-\sqrt{2477.04}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5.2)+\sqrt{2477.04}}{2*-4.9}=\frac{-5.2+\sqrt{2477.04}}{-9.8}
$