(3b-7)(8b+3)=0

Solution for (3b-7)(8b+3)=0 equation:

(3b-7)(8b+3)=0

We multiply parentheses ..

(+24b^2+9b-56b-21)=0

We get rid of parentheses

24b^2+9b-56b-21=0

We add all the numbers together, and all the variables

24b^2-47b-21=0

a = 24; b = -47; c = -21;
Δ = b2-4ac
Δ = -472-4·24·(-21)
Δ = 4225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4225}=65$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-47)-65}{2*24}=\frac{-18}{48}
=-3/8
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-47)+65}{2*24}=\frac{112}{48}
=2+1/3
$