Here is another installment from my review of the June 2012 New York State Math Regents exams.
On the left is a problem from the Algebra 2 / Trigonometry exam; on the right, a problem from the Geometry exam.
Notice that no scale is indicated on any of the graphs here. That is, there is no indication of what “one unit” is equivalent to on any graph.
I admit that I’m pretty sloppy when it comes to labeling graphs, however I know some teachers make accurate labeling and scaling a point of emphasis when it comes to creating graphs. Properly understanding the scale of a graph can be of crucial importance, especially when trying to with questions pertaining to specific numeric values, as in these above.
Tests should stand as models of mathematical content and practice for students; they should not reinforce bad mathematical habits, like ignoring scale.