Answer:
Step-by-step explanation:
[tex]n!=1\cdot2\cdot3\cdot...\cdot n\\\\\dfrac{9!}{(9-2)!}=\dfrac{9!}{7!}=\dfrac{7!\cdot8\cdot9}{7!}\qquad\text{cancel}\ 7!\\\\=8\cdot9=72[/tex]
72