Quadratic Equations (Grade 12 NSC Matric Mathematics): Flashcards

2

$ax^2 + bx + c = 0$

Equation becomes linear (first degree), not quadratic

Factorising, completing the square, quadratic formula

If $(A)(B) = 0$, then either $A = 0$ or $B = 0$

$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$

When quadratic can be easily factored (quickest method)

When factorising not possible or need decimal approximations

Need vertex form or exact answer when factorising is difficult

Substitute known root into equation and solve for unknown