SOLUTION: whats 8^-x/50=2 whats x equal? round answer to 4 decimal places

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Question 979803: whats 8^-x/50=2
whats x equal? round answer to 4 decimal places
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Is this the equation:
+8%5E%28%28-x%29%29+%2F+50+=+2+
If so,
Multiply both sides buy +50+
+8%5E%28%28-x%29%29+=+100+
I can multiply both sides by +8%5Ex+
+8%5E%28%28-x%29%29%2A8%5E%28x%29+=+100%2A8%5Ex+
+8%5E%28%28-x%2Bx%29%29+=+100%2A8%5Ex+
+100%2A8%5Ex+=+1+
+8%5Ex+=+10%5E%28-2%29++
Take the log of both sides
+log%28%28+8%5Ex+%29%29+=+-2+
+x%2Alog%28%288%29%29+=+-2+
+x+=+-2%2Flog%288%29+
--------------------
check:
+log%28%288%29%29+=+.90309+
+x+=+-2%2F.90309+
+x+=+-2.2146+
+8%5E%28%28-x%29%29+%2F+50+=+2+
+8%5E%28%28-%28-2.2146%29%29%29+%2F+50+=+2+
+8%5E2.2146+=+100+
+99.9961+=+100+
error due to rounding off