X^2+4x-86=9

Solution for X^2+4x-86=9 equation:

X^2+4X-86=9

We move all terms to the left:

X^2+4X-86-(9)=0

We add all the numbers together, and all the variables

X^2+4X-95=0

a = 1; b = 4; c = -95;
Δ = b2-4ac
Δ = 42-4·1·(-95)
Δ = 396
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:

$\sqrt{\Delta}=\sqrt{396}=\sqrt{36*11}=\sqrt{36}*\sqrt{11}=6\sqrt{11}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(4)-6\sqrt{11}}{2*1}=\frac{-4-6\sqrt{11}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4)+6\sqrt{11}}{2*1}=\frac{-4+6\sqrt{11}}{2}
$