Question
Determine (8x)of power x if 9 to the power x+2=240+9 to the power x.
Answers
Reiny
The way I read it ...
given: 9^(x+2) = 240 + 9^x , find (8x)^x
9^(x+2) - 9^x = 240
9^x( 9^2 - 1) = 240
9^x * (80) = 240
9^x = 3
9^x = 9^(1/2)
so x = 1/2
the (8x)^(1/2)
= 4^(1/2)
= 2
given: 9^(x+2) = 240 + 9^x , find (8x)^x
9^(x+2) - 9^x = 240
9^x( 9^2 - 1) = 240
9^x * (80) = 240
9^x = 3
9^x = 9^(1/2)
so x = 1/2
the (8x)^(1/2)
= 4^(1/2)
= 2