16=m^2-8m

Solution for 16=m^2-8m equation:

16=m^2-8m

We move all terms to the left:

16-(m^2-8m)=0

We get rid of parentheses

-m^2+8m+16=0

We add all the numbers together, and all the variables

-1m^2+8m+16=0

a = -1; b = 8; c = +16;
Δ = b2-4ac
Δ = 82-4·(-1)·16
Δ = 128
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:

$\sqrt{\Delta}=\sqrt{128}=\sqrt{64*2}=\sqrt{64}*\sqrt{2}=8\sqrt{2}$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(8)-8\sqrt{2}}{2*-1}=\frac{-8-8\sqrt{2}}{-2}
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(8)+8\sqrt{2}}{2*-1}=\frac{-8+8\sqrt{2}}{-2}
$