The conditions x ≥ 0, y ≥ 0 are
called non-negative restrictions In the above example, the set of inequalities (1) to (4)
are constraints Optimisation problem A problem which seeks to maximise or minimise a linear
function (say of two variables x and y) subject to certain constraints as determined by
a set of linear inequalities is called an optimisation problem Linear programming
problems are special type of optimisation problems