-4.9x^2+20x-1.2=0

Solution for -4.9x^2+20x-1.2=0 equation:

-4.9x^2+20x-1.2=0

a = -4.9; b = 20; c = -1.2;
Δ = b2-4ac
Δ = 202-4·(-4.9)·(-1.2)
Δ = 376.48
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{-(20)-\sqrt{376.48}}{2*-4.9}=\frac{-20-\sqrt{376.48}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(20)+\sqrt{376.48}}{2*-4.9}=\frac{-20+\sqrt{376.48}}{-9.8}
$