-0.020x^2-0.7x+50=0

Solution for -0.020x^2-0.7x+50=0 equation:

-0.020x^2-0.7x+50=0

We add all the numbers together, and all the variables

-0.02x^2-0.7x+50=0

a = -0.02; b = -0.7; c = +50;
Δ = b2-4ac
Δ = -0.72-4·(-0.02)·50
Δ = 4.49
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{-(-0.7)-\sqrt{4.49}}{2*-0.02}=\frac{0.7-\sqrt{4.49}}{-0.04}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-0.7)+\sqrt{4.49}}{2*-0.02}=\frac{0.7+\sqrt{4.49}}{-0.04}
$