36=x^2-14x+8

Solution for 36=x^2-14x+8 equation:

36=x^2-14x+8

We move all terms to the left:

36-(x^2-14x+8)=0

We get rid of parentheses

-x^2+14x-8+36=0

We add all the numbers together, and all the variables

-1x^2+14x+28=0

a = -1; b = 14; c = +28;
Δ = b2-4ac
Δ = 142-4·(-1)·28
Δ = 308
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:

$\sqrt{\Delta}=\sqrt{308}=\sqrt{4*77}=\sqrt{4}*\sqrt{77}=2\sqrt{77}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(14)-2\sqrt{77}}{2*-1}=\frac{-14-2\sqrt{77}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(14)+2\sqrt{77}}{2*-1}=\frac{-14+2\sqrt{77}}{-2}
$