9.9x(x-14)=0

Solution for 9.9x(x-14)=0 equation:

9.9x(x-14)=0

We multiply parentheses

9x^2-126x=0

a = 9; b = -126; c = 0;
Δ = b2-4ac
Δ = -1262-4·9·0
Δ = 15876
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{15876}=126$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-126)-126}{2*9}=\frac{0}{18}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-126)+126}{2*9}=\frac{252}{18}
=14
$