Solving quadratic equations using the discriminant

Quadratic equation — is an equation of the form ax2 + bx + c = 0, where a not equal to 0. where D = b2 - 4ac — discriminant of the polynomial ax2 + bx + c.

If D > 0, then the equation has two distinct real roots. If D = 0, then both roots are real and equal. If D < 0, then both roots are complex numbers.