Well we can see that both sides of the equation are just lines, so they can have either zero, one, or infinitely many solutions.
9x-16=9x-23
Since the two lines have the same slope and different y-intercepts, they are parallel lines that will never intersect, thus there are no solutions, mathematically we can go through the process anyway...
9x-16=9x-23 subtract 9x from both sides
-16=-23
Since -16!=-23 the two lines never intersect for any value of x and thus there are no solutions to the equation.