To add or subtract radicals, the degree and radicand must be the same. For example, \(2\sqrt{3} + 3\sqrt{3} = 5\sqrt{3}\) but \(2\sqrt{2} + 2\sqrt{3}\) cannot be added because they have different radicands.
What is \( 3 \)\( \sqrt{18} \) + \( 7 \)\( \sqrt{2} \)
| 21\( \sqrt{2} \) | |
| 16\( \sqrt{2} \) | |
| 10\( \sqrt{9} \) | |
| 21\( \sqrt{9} \) |