solve 5^(2x) - 4(5^x) =12 using log

solve 5^(2x) - 4(5^x) =12 using log. I need to show the work although I know the answer is approximately 1.11
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Let y=5^x then y^2-4y-12=0, so (y-6)(y+2)=0 and y=6 or -2. Therefore 5^x=6 (discard -2 as invalid) and x=log(base 5)6=log6/log5=1.11328 approx., where log to any base will suffice.

 

 

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