The discriminant is a way to find out how many solutions, zeroes, and roots there are in a quadratic equation. The discriminant is an important term to know when dealing with quadratic equations.Essentially, the discriminant is simply this expression: b2-4ac. The discriminate formula is b squared minus four ac for quadratic equation in standard form ax squared plus bx plus c. The formula for the discriminant is simple but powerful: D=b2−4ac. The discriminant tells you about the "nature" of the roots of a quadratic equation given that a, b and c are rational numbers. The discriminant won't tell you what the roots or Solutions of your quadratic equation are but they will tell you what kind of roots they are. Use the quadratic formula u = − b ± b 2 − 4 a c 2 a , where a = 1 , b = − 24 , and c = − 25 . The discriminant b2 − 4ac gives information concerning the nature of the roots (see discriminant). The discriminant in math is defined for polynomials and it is a function of coefficients of polynomials.