2*9^x - 17 *3^x = 9
2*3^2x - 17 *3^x- 9 =0
3^x=t,t>0
2t^2-17t-9=0
D=289+72=361
t1=(17-19)/4=-1/2<0
t2=9
3^x=3^2
x=2
2*9^x - 17 *3^x = 9
2*3^2x - 17 *3^x- 9 =0
3^x=t,t>0
2t^2-17t-9=0
D=289+72=361
t1=(17-19)/4=-1/2<0
t2=9
3^x=3^2
x=2