8z^2-72z=0

Solution for 8z^2-72z=0 equation:

8z^2-72z=0

a = 8; b = -72; c = 0;
Δ = b2-4ac
Δ = -722-4·8·0
Δ = 5184
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5184}=72$
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-72)-72}{2*8}=\frac{0}{16}
=0
$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-72)+72}{2*8}=\frac{144}{16}
=9
$