Tap the blue circles to see an explanation.
| $$ \begin{aligned}4\sqrt{98}+\sqrt{18}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}28\sqrt{2}+3\sqrt{2} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}31\sqrt{2}\end{aligned} $$ | |
| ① | $$ 4 \sqrt{98} =
4 \sqrt{ 7 ^2 \cdot 2 } =
4 \sqrt{ 7 ^2 } \, \sqrt{ 2 } =
4 \cdot 7 \sqrt{ 2 } =
28 \sqrt{ 2 } $$ |
| ② | $$ \sqrt{18} =
\sqrt{ 3 ^2 \cdot 2 } =
\sqrt{ 3 ^2 } \, \sqrt{ 2 } =
3 \sqrt{ 2 }$$ |
| ③ | Combine like terms |