-x^2+10x+70=0

Solution for -x^2+10x+70=0 equation:

-x^2+10x+70=0

We add all the numbers together, and all the variables

-1x^2+10x+70=0

a = -1; b = 10; c = +70;
Δ = b2-4ac
Δ = 102-4·(-1)·70
Δ = 380
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:

$\sqrt{\Delta}=\sqrt{380}=\sqrt{4*95}=\sqrt{4}*\sqrt{95}=2\sqrt{95}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-2\sqrt{95}}{2*-1}=\frac{-10-2\sqrt{95}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+2\sqrt{95}}{2*-1}=\frac{-10+2\sqrt{95}}{-2}
$