The correct answer is 9.42477796077 because pi 3.14ect you would just multiply it by 3 so the answer would be 9.42477796077
Answer:
546
Step-by-step explanation:
Surface Area = 2(lw + lh + wh)
plug in 21 10.5 and 2.5
True, because they make up the two line segments make up the right angle
Answer:

Step-by-step explanation:
Given: ![7-3[(n^{3} +8n)\div (-n)+9n^{2} ]](https://tex.z-dn.net/?f=7-3%5B%28n%5E%7B3%7D%20%2B8n%29%5Cdiv%20%28-n%29%2B9n%5E%7B2%7D%20%5D)
Now simplifying expression using PEDMAS
First solving for small parenthesis.
taking common of n
= ![7-3[n(n^{2} +8)\div (-n)+9n^{2} ]](https://tex.z-dn.net/?f=7-3%5Bn%28n%5E%7B2%7D%20%2B8%29%5Cdiv%20%28-n%29%2B9n%5E%7B2%7D%20%5D)
using law of indices, 
= ![7-3[-(n^{2} +8)+9n^{2} ]](https://tex.z-dn.net/?f=7-3%5B-%28n%5E%7B2%7D%20%2B8%29%2B9n%5E%7B2%7D%20%5D)
Opening parenthesis
= ![7-3[-n^{2} -8+9n^{2} ]](https://tex.z-dn.net/?f=7-3%5B-n%5E%7B2%7D%20-8%2B9n%5E%7B2%7D%20%5D)
= ![7-3[ -8+8n^{2} ]](https://tex.z-dn.net/?f=7-3%5B%20-8%2B8n%5E%7B2%7D%20%5D)
Again using distributive property of multiplication
= 
= 
Hence, the answer is 
Use photomath because it is very helpful bro