The teacher sets a GeoGebra Classroom activity with three pairs of lines in vector form and asks students to decide, for each pair, whether the lines intersect, are parallel or are skew. Students solve the equations in their books first, then enter both lines in the GeoGebra 3D view and rotate it to check their answer. The teacher watches every student's work in the Classroom teacher view, spots students whose algebra says 'intersect' while the 3D view shows skew lines, and brings two of these cases to the board for the class to find the error. Students finish by finding the point of intersection for the pair that does meet.
This page is one of a growing set of PICRAT examples by cell, subject and grade. Page maintained by Andy Perryer.