Question

Determine whether the given values of x is the solution of the given quadratic equation below:

6x² – x – 2 = 0; x = 2/3, - 1

Answer 1

6x² – x – 2 = 0; x = 2/3, - 1

Now put  x = - 1 in L.H.S. of equation.

L.H.S. = 6 × (- 1)2 – ( - 1) – 2

= 6 + 1 – 2

= 7 – 2 = 5 ≠ 0 ≠ R.H.S.

Hence, x = -1 is not a root of the equation.

Put x = 2/3 in L.H.S. of equation.

L.H.S. = 6 × (2/3)² – 2/3 – 2

= 24/9 – 2/3 – 2

= 8/3 – 2/3 – 2 = 0

= 8 – 8 = 0

= R.H.S.

Hence, x = 2/3 is a solution of given equation.