3^(2y-1)+3^(2y-2)-3^(2y-4)=315

Question

3^(2y-1)+3^(2y-2)-3^(2y-4)=315

Answer 1

(З^2у)*(1/3+1/9-1/81)=315
(3^2y)*(27+9-1)=315*81
(3^2y)*(35)=315*81
(3^2y)=9*81
(3^2y)=3^6
2y=6
y=3