Skip to content

CA Foundation · Quantitative Aptitude · Equations

The roots of the equation 2x² − 5x − 3 = 0 are:

The roots are 3 and −1/2. Factorising 2x² − 5x − 3 gives (2x + 1)(x − 3) = 0, so x equals 3 or −1/2. The sum 5/2 and product −3/2 agree with the coefficients of the equation.

  1. A3 and 1/2
  2. B−3 and −1/2
  3. C3 and −1/2Correct
  4. D−3 and 1/2

Explanation

Factorise: 2x² − 6x + x − 3 = 2x(x − 3) + 1(x − 3) = (2x + 1)(x − 3). So x = 3 or x = −1/2. Check: sum = 5/2 and product = −3/2, which match. The option 3 and 1/2 gives product 3/2, so it has the wrong sign.

Did you get it right without looking?

One question tells you little. A timed set on Equations shows your real accuracy, how long you take and where you lose marks.

Practise EquationsFree diagnostic mock

More Equations questions