Quantitative Aptitude  Quadratic Equation  Formula & Concept Tutorial
An equation of the form ax^{2} + bx + c = 0, where a, b and c are real values and a ≠ 0, is called a quadratic equation in variable 'x'.
Here a, b, c are constants.
And x are the variable.
Let root of this quadratic equation is α and β
Therefore α + β = and αβ =
x =
 If b^{2} – 4ac = 0 or Discriminant D = 0 , then root are real and equal .
 If b^{2} – 4ac > 0 or Discriminant D > 0 , then root are real and unequal .
 If b^{2} – 4ac < 0 or Discriminant D < 0 , then root are imaginary and unequal .
For example –
 5x^{2} + 3x + 2 = 0
Using Normal method
Here a = 5, b = 3, c = 2



5x^{2} + 5x – 2x + 2 = 0

5x ( x  1 ) – 2 ( x – 1 ) = 0

( 5x – 2 ) ( x – 1 )

x = 2/5 , x = 1

