To solve this system of equations, we can start by isolating y in the first equation:

3x + y = 3
y = 3 - 3x

Now we substitute this expression for y into the second equation:

log(3)(5x + 4(3 - 3x)) = log(3)(3 - 5)

log(3)(5x + 12 - 12x) = log(3)(-2)

Now we can use the property of logarithms that states log(a)b = log(a)c if b = c. Therefore, we can drop the logarithm terms and solve for x:

5x + 12 - 12x = -2
-7x + 12 = -2
-7x = -14
x = 2

Now that we have found the value of x, we can substitute it back into the first equation to find y:

3(2) + y = 3
6 + y = 3
y = 3 - 6
y = -3

Therefore, the solution to the system of equations is x = 2 and y = -3.