8u(7u+2)=0

Solution for 8u(7u+2)=0 equation:

8u(7u+2)=0

We multiply parentheses

56u^2+16u=0

a = 56; b = 16; c = 0;
Δ = b2-4ac
Δ = 162-4·56·0
Δ = 256
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{256}=16$
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(16)-16}{2*56}=\frac{-32}{112}
=-2/7
$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(16)+16}{2*56}=\frac{0}{112}
=0
$