SOLUTION: If y varies directly as 2x to the power of 3 and y=54 when x =2 . find k

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Question 162894: If y varies directly as 2x to the power of 3 and y=54 when x =2 . find k
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If y varies directly as 2x to the power of 3 and y=54 when x =2
Writing what I think it says: It's 2x^3 not (2x)^3
y = %282x%5E3%29k
:
find k when y = 54 and x=2
54 = %282%2A2%5E3%29k
:
54 = 2(8)k
:
54 = 16k
k = 54%2F16
k = 3.375
:
:
Check solution with this k when x = 2
y = 3.375*2*2^3
y = 3.375(2*8)
y = 3.375*16
y = 54