8(k-6)(7k+4)=0

Solution for 8(k-6)(7k+4)=0 equation:

8(k-6)(7k+4)=0

We multiply parentheses ..

8(+7k^2+4k-42k-24)=0

We multiply parentheses

56k^2+32k-336k-192=0

We add all the numbers together, and all the variables

56k^2-304k-192=0

a = 56; b = -304; c = -192;
Δ = b2-4ac
Δ = -3042-4·56·(-192)
Δ = 135424
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{135424}=368$
$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-304)-368}{2*56}=\frac{-64}{112}
=-4/7
$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-304)+368}{2*56}=\frac{672}{112}
=6
$