4j(12+7j)=0

Solution for 4j(12+7j)=0 equation:

4j(12+7j)=0

We add all the numbers together, and all the variables

4j(7j+12)=0

We multiply parentheses

28j^2+48j=0

a = 28; b = 48; c = 0;
Δ = b2-4ac
Δ = 482-4·28·0
Δ = 2304
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$j_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$j_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2304}=48$
$j_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(48)-48}{2*28}=\frac{-96}{56}
=-1+5/7
$
$j_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(48)+48}{2*28}=\frac{0}{56}
=0
$