Question

Solve the quadratic equation 3x^+4x-4 =0 by the method of completing the square

Answer 1

3x² + 4x - 4 = 0

x² + 4/3x - 4/3 = 0   ...........................(dividing by 3)

x² + 4/3x = 4/3

x² + 2*x*2/3 + 4/9 = 4/3 + 4/9   ...................(adding 4/9 on both sides)

x² + 2*x*2/3 + 2²/3² = 16/9

(x + 2/3)² =  (4/3)²          ..............................[ (a+b)² = a² + b² + 2ab ]

x + 2/3 = 4/3            ..........................(taking square root on both sides)

x = 2/3