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D A E C B
ab=24cm ac =12cm => ad=30cm =>d在ac的反向延长线上,ab=24cm => de=40cm => ae=10cm => ce=2cm
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D A E C B
ab=24cm ac =12cm => ad=30cm =>d在ac的反向延长线上,ab=24cm => de=40cm => ae=10cm => ce=2cm