SOLUTION: 2^(x+3y)= 128 and 2^(3x-y)=2

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Question 256082: 2^(x+3y)= 128 and 2^(3x-y)=2
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
2^(x+3y) = 2^7 ___ x + 3y = 7

2^(3x-y) = 2^1 ___ 3x - y = 1 ___ 9x - 3y = 3

adding eqns ___ 10x = 10 ___ x = 1

substituting ___ 1 + 3y = 7 ___ 3y = 6 ___ y = 2