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 \( 7 \)\( \sqrt{18} \) - \( 9 \)\( \sqrt{2} \)
| 63\( \sqrt{9} \) | |
| 12\( \sqrt{2} \) | |
| -2\( \sqrt{9} \) | |
| -2\( \sqrt{36} \) |