1设y=kx+bA(-1,0),B(0,2)∴b=2,k=2y=2x+22.S△OAB=S△CAB,S△OAB=1/2×OA×OB=1/2×1×2=1S△CAB=1/2×AC×OB=1AC=1C﹙-2.0﹚或﹙1.0﹚S△CAB=1/2×OA×AC=1AC=2C﹙0.√3﹚S△CAB=1/2×AO×BC=1BC=2C﹙0.0﹚