4m*7m=66

Solution for 4m*7m=66 equation:

4m*7m=66

We move all terms to the left:

4m*7m-(66)=0

Wy multiply elements

28m^2-66=0

a = 28; b = 0; c = -66;
Δ = b2-4ac
Δ = 02-4·28·(-66)
Δ = 7392
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:

$\sqrt{\Delta}=\sqrt{7392}=\sqrt{16*462}=\sqrt{16}*\sqrt{462}=4\sqrt{462}$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-4\sqrt{462}}{2*28}=\frac{0-4\sqrt{462}}{56}
=-\frac{4\sqrt{462}}{56}
=-\frac{\sqrt{462}}{14}
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+4\sqrt{462}}{2*28}=\frac{0+4\sqrt{462}}{56}
=\frac{4\sqrt{462}}{56}
=\frac{\sqrt{462}}{14}
$