tolong jawab yaa no. 11-14 sertakan dengan caranya.. makasihh:)

11. (0,5)
12. -b/(2a) = -1, nilai optimum = 7
13. c = 1, a+b = 2, 4a+2b = 6, a = 1, b = 1, y = x^2 + x + 1
14. a+b+c = -2
25a+5b+c = 6
4a+2b+c = -6
18a+3b = 6
21a+3b = 12

3a = 6, a = 2, b = -10, c = 6 y = 2x^2-10x+6