如图,在平面直角坐标系中,,,.
(1)求出的面积.
(2)在图中作出关于轴的对称图形.
(3)写出点A1,B1,C1的坐标.
(1)(2分)S△ABC = (2)(3分)(略)
(3)(3分)A1(1,5),B1(2,0),C1(4,3)