-4.9x^2+2x+850=0

Solution for -4.9x^2+2x+850=0 equation:

-4.9x^2+2x+850=0

a = -4.9; b = 2; c = +850;
Δ = b2-4ac
Δ = 22-4·(-4.9)·850
Δ = 16664
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{16664}=\sqrt{4*4166}=\sqrt{4}*\sqrt{4166}=2\sqrt{4166}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-2\sqrt{4166}}{2*-4.9}=\frac{-2-2\sqrt{4166}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+2\sqrt{4166}}{2*-4.9}=\frac{-2+2\sqrt{4166}}{-9.8}
$