Tap the blue circles to see an explanation.
$$ \begin{aligned}(w+7)(w+1)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}w^2+w+7w+7 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}w^2+8w+7\end{aligned} $$ | |
① | Multiply each term of $ \left( \color{blue}{w+7}\right) $ by each term in $ \left( w+1\right) $. $$ \left( \color{blue}{w+7}\right) \cdot \left( w+1\right) = w^2+w+7w+7 $$ |
② | Combine like terms: $$ w^2+ \color{blue}{w} + \color{blue}{7w} +7 = w^2+ \color{blue}{8w} +7 $$ |