When a=0, the original equation is bx+c=0.

When b≠0, the solution of the original equation is x =-c/b.

When b=0, the solution of the original equation c=0 is an arbitrary real number.

When b=0, the original equation of c≠0 has no real number solution.

When a≠0, the original equation AX 2+BX+C = 0 is a quadratic equation.

Discriminant of root δ = b? -4ac

When δ > 0, the original equation has two unequal real number solutions.

x 1，2=[-b √(b？ -4ac)]/(2a)

When δ = 0, the original equation has two equal real number solutions.

x 1=x2=-b/(2a)

When δ