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

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

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

We add all the numbers together, and all the variables

-3(w-7)(-1w+2)=0

We multiply parentheses ..

-3(-1w^2+2w+7w-14)=0

We multiply parentheses

3w^2-6w-21w+42=0

We add all the numbers together, and all the variables

3w^2-27w+42=0

a = 3; b = -27; c = +42;
Δ = b2-4ac
Δ = -272-4·3·42
Δ = 225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{225}=15$
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-27)-15}{2*3}=\frac{12}{6}
=2
$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-27)+15}{2*3}=\frac{42}{6}
=7
$