SOLUTION: {{{log2(y+4)+log2y=5}}}

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Question 246588: log2%28y%2B4%29%2Blog2y=5
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
log2(y+4)+log2y=5
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log2[y(y+4)] = 5
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log2[y^2+4y] = 5
y^2+4y-25 = 0
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y = [-4 +- sqrt(16 - 4*-25)]/2
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y = [-4 +- sqrt(116)]/2
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y = [-4 +- 2sqrt(29)]/2
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y = [-2 +- sqrt(29)]
===========================
Cheers,
Stan H