Ok so the answer is D because first I solved the equation because you can’t find which answer choice it is equivalent to if you didn’t solve it ... so I solved the equation and got x=-3/2 how I solved this is
3^-x = 3^3x+6 ... since the bases are the same, set the exponents equal
-x=3x+6..... move the variable to the left-hand side and change its side
-x-3x=6 ... collect like terms
-4x = 6..... divide both sides of the equation by -4 and I got x=-3/2
I don’t want this text to be that long so they both seem calculated the same way that’s why i got -3/2 hope that helps;-;