multiply radicals please

Answer:
B
Step-by-step explanation:
[tex]~~~\left( \dfrac 1 3 \sqrt x - \dfrac 32 \sqrt y \right)^2\\\\\\=\left( \dfrac 13 \sqrt x \right)^2 + \left( \dfrac 32 \sqrt y \right)^2 - 2 \left(\dfrac 13 \sqrt x \right)\left( \dfrac 32 \sqrt y \right)\\\\\\=\dfrac 19 x+ \dfrac 94 y-\sqrt{xy}\\\\\\=\dfrac 19x - \sqrt{xy} + \dfrac 94 y[/tex]