Jawabanmu

2014-05-27T20:20:08+07:00
X1*X2 = c/a
2.b = -12/a
b= -6/a

X1+X2 = -b/a
2+b = -5/a
2+(-6/a)=-5/a
a= 1/2

b= -6/a
b= -6/(1/2)
b=-12

4a²-4ab+b² = 4.1/4 - 4 . 1/2 .-12 + 144 = 169