4b(b+5)8=0

Solution for 4b(b+5)8=0 equation:

4b(b+5)8=0

We multiply parentheses

32b^2+160b=0

a = 32; b = 160; c = 0;
Δ = b2-4ac
Δ = 1602-4·32·0
Δ = 25600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25600}=160$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(160)-160}{2*32}=\frac{-320}{64}
=-5
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(160)+160}{2*32}=\frac{0}{64}
=0
$