3X2 + 6x – 17 = 0Calculation:3x2 + 6x – 17 = 0⇒ 3x2 + 6x = 17⇒ 3(x2 + 2x) = 17⇒ (x2 + 2x) = 17/3 ---- (1)Now, (X + 1)2= x2 + 2x + 1= 17/3 + 1= 20/3