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在四边形ABCD中,==(3,4),,则四边形ABCD的面积是 .
在四边形ABCD中,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102526802653130/SYS201311031025268026531015_ST/0.png)
=
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102526802653130/SYS201311031025268026531015_ST/1.png)
=(3,4),
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102526802653130/SYS201311031025268026531015_ST/2.png)
,则四边形ABCD的面积是
.
考点分析:
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