0=-x^2-10x+2

Solution for 0=-x^2-10x+2 equation:

0=-x^2-10x+2

We move all terms to the left:

0-(-x^2-10x+2)=0

We add all the numbers together, and all the variables

-(-x^2-10x+2)=0

We get rid of parentheses

x^2+10x-2=0

a = 1; b = 10; c = -2;
Δ = b2-4ac
Δ = 102-4·1·(-2)
Δ = 108
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:

$\sqrt{\Delta}=\sqrt{108}=\sqrt{36*3}=\sqrt{36}*\sqrt{3}=6\sqrt{3}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-6\sqrt{3}}{2*1}=\frac{-10-6\sqrt{3}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+6\sqrt{3}}{2*1}=\frac{-10+6\sqrt{3}}{2}
$