$$(2+7i)\cdot(-4-8i) = 0$$
Answer
$$ \begin{matrix}i_1 = -\dfrac{ 1 }{ 2 } & i_2 = -\dfrac{ 2 }{ 7 } \\[1 em] \end{matrix} $$
Explanation
$$ \begin{aligned} (2+7i)\cdot(-4-8i) &= 0&& \text{simplify left side} \\[1 em]-8-16i-28i-56i^2 &= 0&& \\[1 em]-56i^2-44i-8 &= 0&& \\[1 em] \end{aligned} $$
$ -56x^{2}-44x-8 = 0 $ is a quadratic equation.
You can use step-by-step quadratic equation solver to see a detailed explanation on how to solve this equation.
This page was created using
Equations Solver