5i(9-9i)=0

Solution for 5i(9-9i)=0 equation:

5i(9-9i)=0

We add all the numbers together, and all the variables

5i(-9i+9)=0

We multiply parentheses

-45i^2+45i=0

a = -45; b = 45; c = 0;
Δ = b2-4ac
Δ = 452-4·(-45)·0
Δ = 2025
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$i_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$i_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2025}=45$
$i_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(45)-45}{2*-45}=\frac{-90}{-90}
=1
$
$i_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(45)+45}{2*-45}=\frac{0}{-90}
=0
$