we have
\(3x+y=18\) -------> equation \(1\)
solve for y
\(y=-3x+18\)
The slope \(m=-3\)
\(3x+y=16\) -------> equation \(2\)
solve for y
\(y=-3x+6\)
The slope \(m=-3\)
The two slopes are the same, so the lines are parallel.
therefore
It's an inconsistent system of equations that has no solution.
the answer is
The system has no solution