在△OAC中,B为AC的中点,若
,则x- y =______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b2613017de2e76bf8dd10295de827ef.png)
![](https://img.xkw.com/dksih/QBM/2018/11/2/2066752918216704/2068893139984384/STEM/4dcff83ce2684052afb057d4d147660f.png?resizew=117)
更新时间:2018-11-05 10:36:46
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【推荐1】已知结论:在平行四边形
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则其中正确的结论是
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