It's a fair question in that a student's inability to give an example of an equation that has no solution indicates that we aren't really teaching students what

It's a fair question in that a student's inability to give an example of an equation that has no solution indicates that we aren't really teaching students what an equation is/means. If one can't instantly give an example of an equation with no solution then they don't really understand what an equation is. Which means something is wrong with our teaching.