3x²-3x-8=0 Selesaikan persamaan kuadrat berikut dengan melengkapi kuadrat sempurna

3x^2 - 3x = 8
x^2 - x = 8/3
x^2 - x + (-1/2)^2 = 8/3 + (-1/2)^2
(x - 1/2)^2 = 35/12
x - 1/2 = +_ √(35/12)
x = 1/2 +_ (1/2)√(35/3)
x = 1/2 +_ (1/2)(1/3)√105
x = 1/2 +_ (1/6)√105
didapat
x = (1/6)(3 + √105) atau x = (1/6)(3 - √105)