How do I do such thing?

Answer:
a= -5
Explanation:
Rewrite the equation to be: 3^a=3^-1 / 3^4
Multiply by adding exponents :))
which would then be 3^a = 3^-5
Then, since the bases are the same then the a would equal negative (-) 5. :))
Hope this helps :)) Plz mark brainlest :))