?A(?1,0),B(3,0),C(0,?3).
又y?(x?1)?4,?顶点M(1····························································· 5分 ,?4). ·容易求得直线CM的表达式是y??x?3. 在y??x?3中,令y?0,得x??3.
·············································································· 6分 ?N(?3,0),?AN?2. ·在y?x?2x?3中,令y??3,得x1?0,x2?2.
22?CP?2,?AN?CP.
···························· 8分 ?3). ·AN∥CP,?四边形ANCP为平行四边形,此时P(2,(3)△AEF是等腰直角三角形.
理由:在y??x?3中,令x?0,得y?3,令y?0,得x?3.
?直线y??x?3与坐标轴的交点是D(0,3),B(3,0).
····································································· 9分 ?OD?OB,??OBD?45°. ·又
点C(0,·········································· 10分 ?3),?OB?OC.??OBC?45°. ·
由图知?AEF??ABF?45°,?AFE??ABE?45°. ··································· 11分
··························· 12分 ??EAF?90°,且AE?AF.?△AEF是等腰直角三角形. ·(4)当点E是直线y??x?3上任意一点时,(3)中的结论成立. 14分
2009年烟台市中考数学试题(含答案)
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