In a ΔABC, A=(1, 2) . Mid–points of AB, AC are respectively (1, −2), (2, 1) . Then B, C are respectively

A(1,2),F(1,−2),E(2,1)   A+B2=F⇒B=2F−A ⇒(2,−4)−(1,2)=(1,−6)                E=A+C2⇒C=2E−A =(4,2)−(1,2)=(3,0)