To solve this equation, we can first simplify it by factoring out a common factor of 6^x:

6^x 6 - 4 6^x = 72
6^x(6 - 4) = 72
6^x(2) = 72

Now, divide both sides by 2:

6^x = 36

Next, rewrite 36 as a power of 6:

6^2 = 36

Therefore, x = 2.

So, the solution to the equation is x = 2.