I've gotten most of my questions answered by looking at the answers people have posted for people in my class, but I'm still confused with two questions. Any help would be very much appreciated!

1. Express the function y= 5^x as an equivalent function with base 3.

2. Prove logab = logcb / logca.

And we were given a hint for this question. Let x= logab, y= logcb and z= logca. Convert these to exponential for...

The work I've done so far for #2 is:

a^x=b

c^y=b

c^z=a

but that's about all I have and I'm not sure where exactly to go from there in the question.

Thank-you for any help!