Tap the blue circles to see an explanation.
| $$ \begin{aligned}-2\sqrt{8}+6\sqrt{8}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}-4\sqrt{2}+12\sqrt{2} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}8\sqrt{2}\end{aligned} $$ | |
| ① | $$ - 2 \sqrt{8} =
-2 \sqrt{ 2 ^2 \cdot 2 } =
-2 \sqrt{ 2 ^2 } \, \sqrt{ 2 } =
-2 \cdot 2 \sqrt{ 2 } =
-4 \sqrt{ 2 } $$ |
| ② | $$ 6 \sqrt{8} =
6 \sqrt{ 2 ^2 \cdot 2 } =
6 \sqrt{ 2 ^2 } \, \sqrt{ 2 } =
6 \cdot 2 \sqrt{ 2 } =
12 \sqrt{ 2 } $$ |
| ③ | Combine like terms |