SOLUTION: Solve 7^-x = 49^x+3 without using logarithms. I can't find anything about this in my book. Please help. Thank you.

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Question 17183: Solve 7^-x = 49^x+3 without using logarithms. I can't find anything about this in my book. Please help. Thank you.
Answer by xcentaur(357) About Me  (Show Source):
You can put this solution on YOUR website!
+7%5E%28-x%29+=+49%5E%28x%2B3%29+
+7%5E%28-x%29+=+%28%28%287%29%5E2%29%5E%28x%2B3%29%29+
+7%5E%28-x%29+=+7%5E%282%28x%2B3%29%29+
equating the bases we get,
-x=2(x+3)
-x=2x+6
-3x=6
x=-2


Hope this helps,
Prabhat