1000x^2-100x-21=0

Solution for 1000x^2-100x-21=0 equation:

1000x^2-100x-21=0

a = 1000; b = -100; c = -21;
Δ = b2-4ac
Δ = -1002-4·1000·(-21)
Δ = 94000
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:

$\sqrt{\Delta}=\sqrt{94000}=\sqrt{400*235}=\sqrt{400}*\sqrt{235}=20\sqrt{235}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-100)-20\sqrt{235}}{2*1000}=\frac{100-20\sqrt{235}}{2000}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-100)+20\sqrt{235}}{2*1000}=\frac{100+20\sqrt{235}}{2000}
$