Answer
$$z=2,\:y=1,\:x=3$$
Work Step by Step
Solving the system of equations using substitution, we find:
$$3\cdot \frac{5+3\cdot \frac{-5z+13}{3}-z}{2}-\frac{-5z+13}{3}+2z=12 \\ z=2 \\ y=\frac{-5\cdot \:2+13}{3} \\ y=1 \\ x=\frac{5+3\cdot \:1-2}{2}=3$$