已知：如图，直线l 1 与y轴交点坐标为（0，-1），直线l 2 与x轴交点坐标为（3，0），两直线交点为P（1，1 如图，已知直线l 1 ：y=-x+2与直线l 2 ：y=2x...
\u5982\u56fe\uff0c\u76f4\u7ebfl1\u3001l2\u76f8\u4ea4\u4e8e\u70b9A\uff0cl1\u4e0ex\u8f74\u7684\u4ea4\u70b9\u5750\u6807\u4e3a\uff08-1\uff0c0\uff09\uff0cl2\u4e0ey\u8f74\u7684\u4ea4\u70b9\u5750\u6807\u4e3a\uff080\uff0c-2\uff09\uff0c\u7ed3\u5408\u56fe\u8c61\u89e3\uff081\uff09\u8bbe\u76f4\u7ebfl2\u8868\u793a\u7684\u4e00\u6b21\u51fd\u6570\u8868\u8fbe\u5f0f\u4e3ay=kx+b\uff0e\u2235x=0\u65f6\uff0cy=-2\uff1bx=2\u65f6\uff0cy=3\uff0e\u2234?2\uff1db3\uff1d2k+b\uff082\u5206\uff09\u2234k\uff1d52b\uff1d?2\uff083\u5206\uff09\u2234\u76f4\u7ebfl2\u8868\u793a\u7684\u4e00\u6b21\u51fd\u6570\u8868\u8fbe\u5f0f\u662fy=52x-2\uff0e\uff084\u5206\uff09\uff082\uff09\u4ece\u56fe\u8c61\u53ef\u4ee5\u77e5\u9053\uff0c\u5f53x\uff1e-1\u65f6\uff0c\u76f4\u7ebfl1\u8868\u793a\u7684\u4e00\u6b21\u51fd\u6570\u7684\u51fd\u6570\u503c\u5927\u4e8e0\uff0e\uff085\u5206\uff09\u5f5352x-2=0\uff0c\u5f97x=45\uff0e\u2234\u5f53x\uff1e45\u65f6\uff0c\u76f4\u7ebfl2\u8868\u793a\u7684\u4e00\u6b21\u51fd\u6570\u7684\u51fd\u6570\u503c\u5927\u4e8e0\uff0e\uff087\u5206\uff09\u2234\u5f53x\uff1e45\u65f6\uff0cl1\u3001l2\u8868\u793a\u7684\u4e24\u4e2a\u4e00\u6b21\u51fd\u6570\u7684\u51fd\u6570\u503c\u90fd\u5927\u4e8e0\uff0e\uff088\u5206\uff09
\u89e3\uff1a\uff081\uff09\u7531\u9898\u610f\u5f97 \uff0c\u89e3\u5f97x=-2\uff0cy=4\uff0c\u2234F\u70b9\u5750\u6807\uff1a\uff08-2\uff0c4\uff09\uff1b\u8fc7F\u70b9\u4f5c\u76f4\u7ebfFM\u5782\u76f4X\u8f74\u4ea4x\u8f74\u4e8eM\uff0cME=MF=4\uff0c\u25b3MEF\u662f\u7b49\u8170\u76f4\u89d2\u4e09\u89d2\u5f62\uff0c\u2220GEF=45\u00b0\uff1b\uff082\uff09\u7531\u56fe\u53ef\u77e5G\u70b9\u7684\u5750\u6807\u4e3a\uff08-4\uff0c0\uff09\uff0c\u5219C\u70b9\u7684\u6a2a\u5750\u6807\u4e3a-4\uff0c\u2235\u70b9C\u5728\u76f4\u7ebfl 1 \u4e0a\uff0c\u2234\u70b9C\u7684\u5750\u6807\u4e3a\uff08-4\uff0c6\uff09\uff0c\u2235\u7531\u56fe\u53ef\u77e5\u70b9D\u4e0e\u70b9C\u7684\u7eb5\u5750\u6807\u76f8\u540c\uff0c\u4e14\u70b9D\u5728\u76f4\u7ebfl 2 \u4e0a\uff0c\u2234\u70b9D\u7684\u5750\u6807\u4e3a\uff08-1\uff0c6\uff09\uff0c\u2235\u7531\u56fe\u53ef\u77e5\u70b9A\u4e0e\u70b9D\u7684\u6a2a\u5750\u6807\u76f8\u540c\uff0c\u4e14\u70b9A\u5728x\u8f74\u4e0a\uff0c\u2234\u70b9A\u7684\u5750\u6807\u4e3a\uff08-1\uff0c0\uff09\uff0c\u2234DC=|-1-\uff08-4\uff09|=3\uff0cBC=6\uff1b\uff083\uff09\u2235\u70b9E\u662fl 1 \u4e0ex\u8f74\u7684\u4ea4\u70b9\uff0c\u2234\u70b9E\u7684\u5750\u6807\u4e3a\uff082\uff0c0\uff09\uff0cS \u25b3GFE = = =12\uff0c\u82e5\u77e9\u5f62ABCD\u4ece\u539f\u5730\u51fa\u53d1\uff0c\u6cbfx\u8f74\u6b63\u65b9\u5411\u4ee5\u6bcf\u79d21\u4e2a\u5355\u4f4d\u957f\u5ea6\u7684\u901f\u5ea6\u5e73\u79fb\uff0c\u5f53t\u79d2\u65f6\uff0c\u79fb\u52a8\u7684\u8ddd\u79bb\u662f1\u00d7t=t\uff0c\u5219B\u70b9\u7684\u5750\u6807\u4e3a\uff08-4+t\uff0c0\uff09\uff0cA\u70b9\u7684\u5750\u6807\u4e3a\uff08-1+t\uff0c0\uff09\uff1b\u2460\u5728\u8fd0\u52a8\u5230t\u79d2\uff0c\u82e5BC\u8fb9\u4e0el2\u76f8\u4ea4\u8bbe\u4ea4\u70b9\u4e3aN\uff0cAD\u4e0el 1 \u76f8\u4ea4\u8bbe\u4ea4\u70b9\u4e3aK\uff0c\u90a3\u4e48-4\u2264-4+t\u2264-2\uff0c\u53730\u2264t\u22642\u65f6\uff0eN\u70b9\u7684\u5750\u6807\u4e3a\uff08-4+t\uff0c2t\uff09\uff0cK\u70b9\u7684\u5750\u6807\u4e3a\uff08-1+t\uff0c3-t\uff09\uff0cS=S \u25b3GFE -S \u25b3GNB -S \u25b3AEK =12- = \uff0c\u2461\u5728\u8fd0\u52a8\u5230t\u79d2\uff0c\u82e5BC\u8fb9\u4e0el1\u76f8\u4ea4\u8bbe\u4ea4\u70b9\u4e3aN\uff0cAD\u4e0el 1 \u76f8\u4ea4\u8bbe\u4ea4\u70b9\u4e3aK\uff0c\u90a3\u4e48-2\uff1c-4+t\u4e14-1+t\u22643\uff0c\u53732\uff1ct\u22644\u65f6\uff0cN\u70b9\u7684\u5750\u6807\u4e3a\uff08-4+t\uff0c6-t\uff09\uff0cK\u70b9\u7684\u5750\u6807\u4e3a\uff08-1+t\uff0c3-t\uff09\uff0cS=S \u68af\u5f62BNKA = = \uff0c\u2462\u5728\u8fd0\u52a8\u5230t\u79d2\uff0c\u82e5BC\u8fb9\u4e0el1\u76f8\u4ea4\u8bbe\u4ea4\u70b9\u4e3aN\uff0cAD\u4e0el 1 \u4e0d\u76f8\u4ea4\uff0c\u90a3\u4e48-4+t\u22643\u4e14\ufe631+t\uff1e3\uff0c\u53734\uff1ct\u22647\u65f6\uff0cN\u70b9\u7684\u5750\u6807\u4e3a\uff08-4+t\uff0c6-t\uff09\uff0cS=S \u25b3BNE = = \uff0c\u7b54\uff1a\uff081\uff09F\u70b9\u5750\u6807\uff1a\uff08-2\uff0c4\uff09\uff0c\u2220GEF\u7684\u5ea6\u6570\u662f45\u00b0\uff1b\uff082\uff09\u77e9\u5f62ABCD\u7684\u8fb9DC\u7684\u957f\u4e3a3\uff0cBC\u7684\u957f\u4e3a6\uff1b\uff083\uff09s\u5173\u4e8et\u7684\u51fd\u6570\u5173\u7cfb\u5f0f \u3002
（1）设直线l 1 的解析式为y=kx+b，由题意得：
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