【導(dǎo)讀】,正方形ABCD的頂點(diǎn)A在x軸的正半軸上,頂點(diǎn)B在y軸的負(fù)半軸上,,四邊形ABCD個頂點(diǎn)坐標(biāo)分別為A,B,C,D(3,1),則這個四。,將△ABC繞點(diǎn)C旋轉(zhuǎn)180°得到△,設(shè)旋轉(zhuǎn)后點(diǎn)的坐標(biāo)為(a,b),則旋轉(zhuǎn)前點(diǎn)。,在直角坐標(biāo)系中,OABC是正方形,點(diǎn)A的坐標(biāo)是(4,0),點(diǎn)P為邊AB上一點(diǎn),∠CPB=60°,