simplify the radical expression.
7. √63x^15y^9/7xy^11




8. √3+4√3
5√6
5√3
3√6
3√3




9. 2√6+3√96
14√6
14√96
5√96
50√6



10. (8 +√11 )(8 –√11 )
53
75 + 16√11
–57
64 + √11