• Resultant[, , var]
• Resultant[, , var, Modulus->p]
Here is the resultant with respect to y of two polynomials in x and y. The original polynomials have a common root in y only for values of x at which the resultant vanishes.
Here Resultant is used to define Discriminant. The discriminant of a polynomial is the product of the squares of all the differences of the roots taken in pairs.
This gives the discriminant for a fifth degree polynomial.