the question is in the photo

Answer:
8 goes in the first box
3 goes in the second box
The expression is [tex]\frac{8}{3}x^4y[/tex]
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Work Shown:
[tex]z = 9xy * \left(\frac{2}{3}x\right)^3\\\\z = 9xy * \frac{2^3}{3^3}x^3\\\\z = 9xy * \frac{8}{27}x^3\\\\z = 9*\frac{8}{27}*x*x^3*y\\\\z = \frac{9*8}{27}*x^4y\\\\z = \frac{9*8}{9*3}*x^4y\\\\z = \frac{8}{3}x^4y\\\\[/tex]