7m^2+72m+81=0

Solution for 7m^2+72m+81=0 equation:

7m^2+72m+81=0

a = 7; b = 72; c = +81;
Δ = b2-4ac
Δ = 722-4·7·81
Δ = 2916
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2916}=54$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(72)-54}{2*7}=\frac{-126}{14}
=-9
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(72)+54}{2*7}=\frac{-18}{14}
=-1+2/7
$