-(3u-2)(u+7)=0

Solution for -(3u-2)(u+7)=0 equation:

-(3u-2)(u+7)=0

We multiply parentheses ..

-(+3u^2+21u-2u-14)=0

We get rid of parentheses

-3u^2-21u+2u+14=0

We add all the numbers together, and all the variables

-3u^2-19u+14=0

a = -3; b = -19; c = +14;
Δ = b2-4ac
Δ = -192-4·(-3)·14
Δ = 529
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{529}=23$
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-19)-23}{2*-3}=\frac{-4}{-6}
=2/3
$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-19)+23}{2*-3}=\frac{42}{-6}
=-7
$