Answer:

Step-by-step explanation:
![Volume\:of\:cube:V=a^{3} \:(a\:is\:the\:length\:of\:each\:edge)\\\Leftrightarrow a=\sqrt[3]{V} \Leftrightarrow a=\sqrt[3]{729} =9](https://tex.z-dn.net/?f=Volume%5C%3Aof%5C%3Acube%3AV%3Da%5E%7B3%7D%20%5C%3A%28a%5C%3Ais%5C%3Athe%5C%3Alength%5C%3Aof%5C%3Aeach%5C%3Aedge%29%5C%5C%5CLeftrightarrow%20a%3D%5Csqrt%5B3%5D%7BV%7D%20%5CLeftrightarrow%20a%3D%5Csqrt%5B3%5D%7B729%7D%20%3D9)
10 pieces of silverware laid in a row if 3 are identical spoons, 4 are identical forks, and 3 are identical knifes
The arrangement of 'm' objects on which 'n' objects are of same kind is 
Given: 10 pieces of silverware so its 10!
3 are identical spoons so its 3!
4 are identical forks so its 4!
and 3 are identical knifes so its 3!
Arrangements made =
= 4200
Answer:
x = 5
Step-by-step explanation:
First you distribute
9x - 21 = 24
Add 21 to both sides
9x = 45
Divide both sides by 9
x = 5