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Determine (8x)^x , if 9^(x+2)=240+9^x...

Determine `(8x)^x ,` if `9^(x+2)=240+9^x`

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given that `9^(x+2)=240+9^x`
`9^(x+2)-9^x=240`
`9^x(9^2-1)=240`
so `9^x=3`
or `3^(2x)=3`or `x=1/2`
so `(8x)^x=(8xx1/2)^(1/2)=2`
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