Let equation of parabola is y=ax2+bx+c . . . (i) Eq. (i) passes through (1,−3),(−1,5) and (0,2). So, ‌‌a+b+c=−3‌‌... (ii) ⇒‌‌a−b+c=5. . . (iii) ⇒c=2. . . (iv) From Eqs. (ii), (iii) and (iv), From Eq. (i), ‌‌a=−1,b=−4,c=2 ∵(2,k) lies on the above parabola. ∵(2,k) lies on the above parabola. ∴‌‌k=−4−8+2=−10