Solve the equation

Question

3^2x - 12 x 3^x + 27 = 0

Answer 1

let 3^x = y
so we get

y^2 - 12y + 27 = 0
(y-3)(y-9) = 0
y = 3 or y = 9
then
x^2 = 3 or x^2 = 9
x = ± √3 or x = ± 3

btw, in something like 12 x 3^x , do not use x as a multiplication sign, especially if you have a variable x
either say just 12(3^x) or say 12*3^x