SOLUTION: okay i need help with this one: 49^x = 7^(x^2)-15 thanks!

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Question 115904: okay i need help with this one:
49^x = 7^(x^2)-15

thanks!
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
49%5Ex+=+7%5E%28x%5E2-15%29
If I copied it right
7%5E%282x%29+=+7%5E%28x%5E2+-+15%29
2x+=+x%5E2+-+15
x%5E2+-+2x+-+15+=+0
%28x+-+5%29%28x+%2B+3%29+=+0
x+=+5
x+=+-3
check answers
49%5Ex+=+7%5E%28x%5E2-15%29
49%5E5+=+7%5E%285%5E2-15%29
7%5E10+=+7%5E%2825-15%29
7%5E10+=+7%5E10
and
49%5E-3+=+7%5E%28%28-3%29%5E2-15%29
7%5E-6+=+7%5E%289-15%29
7%5E-6+=+7%5E-6
OK