WhAt is x

3x9^x=81

2 answers

I assume the left reads three times nine to the x power.

3*9^x=3*3^2x=3^(2x+1)

3^(2x+1)=81
take the log base three of both sides.

2x+1=4
2x=3
x=1.5

weird problem
or

3x9^x=81 , divide both sides by 3
9^x= 27
(3^2)^x = 3^3
3^(2x) = 3^3
2x = 3
x = 3/2 = 1.5