Answer:
Step-by-step explanation:
to find the answer you have to find the vulume and then divide by 450
Hello there!
a = 11 + 4b - 4c
a = 4b - 4c + 11
a + (-a + 4c) = (4b - 4c + 11) + (-a + 4c)
Hope This Helps You!Good Luck :)

get rid of -2 by subtracting it from 21

Now you get your answer

Hope this helps! :)