Hep me ASAP!!!! A.-2 B.4 C.7-3sqrt3 D.7- sqrt3

Answer:
7 - 3[tex]\sqrt{3}[/tex]
Step-by-step explanation:
Given
3 + [tex]\sqrt{x+7}[/tex] - [tex]\sqrt{3x}[/tex] ← substitute x = 9
= 3 + [tex]\sqrt{16}[/tex] - [tex]\sqrt{27}[/tex]
= 3 + 4 - [tex]\sqrt{9(3)}[/tex]
= 7 - 3[tex]\sqrt{3}[/tex]