m(m+4)=10

Solution for m(m+4)=10 equation:

m(m+4)=10

We move all terms to the left:

m(m+4)-(10)=0

We multiply parentheses

m^2+4m-10=0

a = 1; b = 4; c = -10;
Δ = b2-4ac
Δ = 42-4·1·(-10)
Δ = 56
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:

$\sqrt{\Delta}=\sqrt{56}=\sqrt{4*14}=\sqrt{4}*\sqrt{14}=2\sqrt{14}$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(4)-2\sqrt{14}}{2*1}=\frac{-4-2\sqrt{14}}{2}
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4)+2\sqrt{14}}{2*1}=\frac{-4+2\sqrt{14}}{2}
$