2s(9s+7)=0

Solution for 2s(9s+7)=0 equation:

2s(9s+7)=0

We multiply parentheses

18s^2+14s=0

a = 18; b = 14; c = 0;
Δ = b2-4ac
Δ = 142-4·18·0
Δ = 196
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$s_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$s_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{196}=14$
$s_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(14)-14}{2*18}=\frac{-28}{36}
=-7/9
$
$s_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(14)+14}{2*18}=\frac{0}{36}
=0
$