Representing inequalities graphically

This resource develops the concept of representing inequalities on a Cartesian coordinate grid. Students work with algebraic representations in a variety of formats and then shade the relevant areas.

An initial activity is to play a game ‘Hunting the target’. This involves students being given inequalities that they draw represent on a coordinate grid. The challenge is to find the ‘target’ point that satisfies all of the inequalities given.

The next task is to play the game ‘Give us a clue’. This is the reverse of ‘Hunting the target’ in that students choose a point and then try and give the minimum number of inequalities to allow another player to establish the point.

The lesson assumes that students are familiar with the equation for a straight line being given in a variety of formats.

There are pre-lesson and post-lesson formative assessment tasks. Detailed teacher notes give suggestions on questioning and how to use the resources. Full solutions are given for each of the sections.

This is a concept development lesson from the Mathematics Assessment Resource Service, a collaboration between UC Berkeley and the Shell Centre team at the University of Nottingham. Further information on the collection is given here.