Thread: Indices (simple but i am have problems)

9^x+1 - 13(3^x) + 4 =0

Use y = 3^x

OK so i start and reached to this point
3^2(x+1) - 13(3^x) + 4 = 0


3^2x+2 - 13(3^x) + 4 = 0

I need some help to proceed, thanks in advance

Expand:



Which becomes (from the rules of indices - look at the first term):



Now use the hint and substitute



So:



Can you solve for and put the solution back in terms of now?