Tap the blue circles to see an explanation.
| $$ \begin{aligned}\sqrt{98}+2\sqrt{18}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}7\sqrt{2}+6\sqrt{2} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}13\sqrt{2}\end{aligned} $$ | |
| ① | $$ \sqrt{98} =
\sqrt{ 7 ^2 \cdot 2 } =
\sqrt{ 7 ^2 } \, \sqrt{ 2 } =
7 \sqrt{ 2 }$$ |
| ② | $$ 2 \sqrt{18} =
2 \sqrt{ 3 ^2 \cdot 2 } =
2 \sqrt{ 3 ^2 } \, \sqrt{ 2 } =
2 \cdot 3 \sqrt{ 2 } =
6 \sqrt{ 2 } $$ |
| ③ | Combine like terms |