9t(9t+8)=0

Solution for 9t(9t+8)=0 equation:

9t(9t+8)=0

We multiply parentheses

81t^2+72t=0

a = 81; b = 72; c = 0;
Δ = b2-4ac
Δ = 722-4·81·0
Δ = 5184
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5184}=72$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(72)-72}{2*81}=\frac{-144}{162}
=-8/9
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(72)+72}{2*81}=\frac{0}{162}
=0
$