Tap the blue circles to see an explanation.
$$ \begin{aligned}(-11-7i)\cdot(2+6i)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}-22-66i-14i-42i^2 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}-42i^2-80i-22\end{aligned} $$ | |
① | Multiply each term of $ \left( \color{blue}{-11-7i}\right) $ by each term in $ \left( 2+6i\right) $. $$ \left( \color{blue}{-11-7i}\right) \cdot \left( 2+6i\right) = -22-66i-14i-42i^2 $$ |
② | Combine like terms: $$ -22 \color{blue}{-66i} \color{blue}{-14i} -42i^2 = -42i^2 \color{blue}{-80i} -22 $$ |