Tap the blue circles to see an explanation.
| $$ \begin{aligned}(h+4)(h+4)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}h^2+4h+4h+16 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}h^2+8h+16\end{aligned} $$ | |
| ① | Multiply each term of $ \left( \color{blue}{h+4}\right) $ by each term in $ \left( h+4\right) $. $$ \left( \color{blue}{h+4}\right) \cdot \left( h+4\right) = h^2+4h+4h+16 $$ |
| ② | Combine like terms: $$ h^2+ \color{blue}{4h} + \color{blue}{4h} +16 = h^2+ \color{blue}{8h} +16 $$ |