-3m^2+10m+81=0

Solution for -3m^2+10m+81=0 equation:

-3m^2+10m+81=0

a = -3; b = 10; c = +81;
Δ = b2-4ac
Δ = 102-4·(-3)·81
Δ = 1072
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:

$\sqrt{\Delta}=\sqrt{1072}=\sqrt{16*67}=\sqrt{16}*\sqrt{67}=4\sqrt{67}$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-4\sqrt{67}}{2*-3}=\frac{-10-4\sqrt{67}}{-6}
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+4\sqrt{67}}{2*-3}=\frac{-10+4\sqrt{67}}{-6}
$