SOLUTION: Please help us solve: 9^(2x+3)=2187 Keep getting negative number. Thanks Pat

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Question 720371: Please help us solve:
9^(2x+3)=2187
Keep getting negative number.
Thanks
Pat
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+9%5E%28+2x+%2B+3+%29+=+2187+
+9%5E%28+2x+%2B+3+%29+=+3%5E7+
+%283%5E2%29%5E%28+2x+%2B+3+%29+=+3%5E7+
+3%5E%28+2%2A%28+2x+%2B+3+%29+%29+=+3%5E7+
+3%5E%28+4x+%2B+6+%29+=+3%5E7+
The exponents must be the same on both sides
+4x+%2B+6+=+7+
+4x+=+1+
+x+=+1%2F4+
-----------
check:
+9%5E%28+2x+%2B+3+%29+=+2187+
+9%5E%28+2%2A%281%2F4%29+%2B+3+%29+=+2187+
+9%5E%28+1%2F2+%2B+3+%29+=+2187+
+9%5E%28+7%2F2+%29+=+2187+
+%289%5E%281%2F2%29%29%5E7+=+2187+
+3%5E7+=+2187+
+3%5E7+=+3%5E7+
OK