(4w+7)(3-w)=0

Solution for (4w+7)(3-w)=0 equation:

(4w+7)(3-w)=0

We add all the numbers together, and all the variables

(4w+7)(-1w+3)=0

We multiply parentheses ..

(-4w^2+12w-7w+21)=0

We get rid of parentheses

-4w^2+12w-7w+21=0

We add all the numbers together, and all the variables

-4w^2+5w+21=0

a = -4; b = 5; c = +21;
Δ = b2-4ac
Δ = 52-4·(-4)·21
Δ = 361
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{361}=19$
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(5)-19}{2*-4}=\frac{-24}{-8}
=+3
$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5)+19}{2*-4}=\frac{14}{-8}
=-1+3/4
$