m^2=6m+20

Solution for m^2=6m+20 equation:

m^2=6m+20

We move all terms to the left:

m^2-(6m+20)=0

We get rid of parentheses

m^2-6m-20=0

a = 1; b = -6; c = -20;
Δ = b2-4ac
Δ = -62-4·1·(-20)
Δ = 116
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{116}=\sqrt{4*29}=\sqrt{4}*\sqrt{29}=2\sqrt{29}$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-6)-2\sqrt{29}}{2*1}=\frac{6-2\sqrt{29}}{2}
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6)+2\sqrt{29}}{2*1}=\frac{6+2\sqrt{29}}{2}
$