Describe the 3 types of solution to a quadratic equation

  • The behaviour of the solution depends on the value of the discriminant, D = b2 – 4ac, (aptly named as it allows you to discriminate between solutions)

  • If D > 0: The equation has real roots (the parabola will intersect the x axis twice)

  • If D = 0: The equation has a repeated real root (the vertex of the parabola lies on the x axis)

  • If D < 0: The equation has no real roots but rather 2 complex roots (the parabola does not intersect the x axis)

GL

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