SOLUTION: Solve the simultaneous equations giving your answer in logarithmic form: 3^(X-y) = 9^y 2^X = 6(2^y)

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Question 1043767: Solve the simultaneous equations giving your answer in logarithmic form:
3^(X-y) = 9^y
2^X = 6(2^y)
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the simultaneous equations giving your answer in logarithmic form:
3%5E%28X-y%29+=+9%5Ey
2%5EX+=+6%282%5Ey%29
:
we can greatly simplify the 1st equation; 9 = 3^2, therefore we can write it
3%5E%28X-y%29+=+3%5E%282y%29
therefore
x - y = 2y
x = 3y
the 2nd equation
2%5EX+=+6%282%5Ey%29
2%5Ex%2F2%5Ey = 6
Replace x with 3y
2%283y%29%2F2%5Ey = 6
therefore
2%5E%282y%29 = 6
2y*log(2) = log(6)
2y = log%286%29%2Flog%282%29
2y = 2.525
y = 2.525/2
y = 1.2925
Find x
x = 3(1.2925)
x = 3.877
But they want it in logarithmic form
log(x) = .5885
log(y) = .1114