which makes clear the roots of the equation 
i.e. any values of 
at which the graph of the function 
intersects the -axis. [M1.3, M1.4]
of: a polynomial function (especially a quadratic function)
is: the form which makes clear the roots of the equation i.e. any values of at which the graph of the function intersects the -axis. [M1.3, M1.4]
See factorization.
Copyright 1997, The Open University