Tap the blue circles to see an explanation.
| $$ \begin{aligned}-5\sqrt{11}-2\sqrt{99}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}-5\sqrt{11}-6\sqrt{11} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}-11\sqrt{11}\end{aligned} $$ | |
| ① | $$ - 2 \sqrt{99} =
-2 \sqrt{ 3 ^2 \cdot 11 } =
-2 \sqrt{ 3 ^2 } \, \sqrt{ 11 } =
-2 \cdot 3 \sqrt{ 11 } =
-6 \sqrt{ 11 } $$ |
| ② | Combine like terms |