![](https://static.youtibao.com/asksite/comm/h5/images/m_q_title.png)
[单选题]
如图,在□ABCD中,对角线AC和BD相交于点O,△AOB的周长为15,AB=6,则对角线AC、BD的长度的和是()
A.9
B.18
C.27
D.36
![](https://static.youtibao.com/asksite/comm/h5/images/m_q_a.png)
B、18
![](https://static.youtibao.com/asksite/comm/h5/images/solist_ts.png)
A.9
B.18
C.27
D.36
B、18
A.1个
B.2个
C.3个
D.4个
A.16
B.6.25
C.9
D.25
A.选①②
B.选①③
C.选②③
D.选②④
A.对角线AC平分对角线bd且AC垂直BD
B.对角线AC平分对角线bd且角a等于角C
C.对角线AC平分对角线bd且平分角a和角c
D.对角线AC平分角A和角c,且角a等于角c