1.75x^2-4x-100=0

Solution for 1.75x^2-4x-100=0 equation:

1.75x^2-4x-100=0

a = 1.75; b = -4; c = -100;
Δ = b2-4ac
Δ = -42-4·1.75·(-100)
Δ = 716
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:

$\sqrt{\Delta}=\sqrt{716}=\sqrt{4*179}=\sqrt{4}*\sqrt{179}=2\sqrt{179}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-4)-2\sqrt{179}}{2*1.75}=\frac{4-2\sqrt{179}}{3.5}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+2\sqrt{179}}{2*1.75}=\frac{4+2\sqrt{179}}{3.5}
$