4x+72=x^2+6

Solution for 4x+72=x^2+6 equation:

4x+72=x^2+6

We move all terms to the left:

4x+72-(x^2+6)=0

We get rid of parentheses

-x^2+4x-6+72=0

We add all the numbers together, and all the variables

-1x^2+4x+66=0

a = -1; b = 4; c = +66;
Δ = b2-4ac
Δ = 42-4·(-1)·66
Δ = 280
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:

$\sqrt{\Delta}=\sqrt{280}=\sqrt{4*70}=\sqrt{4}*\sqrt{70}=2\sqrt{70}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(4)-2\sqrt{70}}{2*-1}=\frac{-4-2\sqrt{70}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4)+2\sqrt{70}}{2*-1}=\frac{-4+2\sqrt{70}}{-2}
$