中学生网络课堂本课配套习题挑战模式1/5
单选题
难度系数：
1.若两个相似三角形的面积之比为1：4，则它们的周长之比为（ ）
| A: 1：2 |
| B: 1：4 |
| C: 1：5 |
| D: 1：16 |
一次做对，真牛！
+5奖励规则>
- 提示1：IOebuOS8vOS4ieinkuW9oumdouenr+eahOavlOetieS6juebuOS8vOS4ieinkuW9ouWRqOmVv+avlOeahOW5s+aWuQ==
- 答案：QQ==
6Kej77ya5qC55o2u55u45Ly85LiJ6KeS5b2i6Z2i56ev55qE5q+U562J5LqO55u45Ly85LiJ6KeS5b2i5ZGo6ZW/5q+U55qE5bmz5pa5PGJyPuKItOWRqOmVv+eahOavlOS4ujHvvJoy
本课配套习题挑战模式2/5
单选题
难度系数：
2.
如图，∠ABD=∠BDC=90°，∠A=∠CBD，AB=3，BD=2，则CD的长为（ ）
| A:
|
| B:
|
| C: 2 |
| D: 3 |
一次做对，真牛！
+5奖励规则>
- 提示1：PHA+5YWI5qC55o2u6aKY5oSP5Yik5pat5Ye64pazQUJE4oi94pazQkRD77yM5YaN5qC55o2u55u45Ly85LiJ6KeS5b2i55qE5a+55bqU6L655oiQ5q+U5L6L5Y2z5Y+v5b6X5Ye6Q0TnmoTplb8uPC9wPg==
- 答案：Qg==
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
本课配套习题挑战模式3/5
单选题
难度系数：
3.
如图，D是△ABC的边BC上一点，已知AB=4，AD=2. ∠DAC=∠B，若△ABD的面积为a，则△ACD的面积为（ ）
| A:
|
| B:
|
| C:
|
| D:
|
一次做对，真牛！
+5奖励规则>
- 提示1：PHA+6aaW5YWI6K+B5piO4pazQUNE4oi94pazQkNB77yM55Sx55u45Ly85LiJ6KeS5b2i55qE5oCn6LSo5Y+v5b6X77ya4pazQUNE55qE6Z2i56ev77ya4pazQUJD55qE6Z2i56ev5Li6Me+8mjTvvIzlm6DkuLrilrNBQkTnmoTpnaLnp6/kuLph77yM6L+b6ICM5rGC5Ye64pazQUNE55qE6Z2i56evLjwvcD4=
- 答案：Qw==
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
本课配套习题挑战模式4/5
单选题
难度系数：
4.
如图，四边形ABCD四边的中点分别为E，F，G，H，对角线AC与BD相交于点O，若四边形EFGH的面积是3，则四边形ABCD的面积是（ ）
| A: 3 |
| B: 6 |
| C: 9 |
| D: 12 |
一次做对，真牛！
+5奖励规则>
- 提示1：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
- 答案：Qg==
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
本课配套习题挑战模式5/5
单选题
难度系数：
5.
如图，梯形ABCD中，AD∥BC，对角线AC、BD相交于O，AD=1，BC=4，则△AOD与△BOC的面积比等于（ ）
| A:
|
| B:
|
| C:
|
| D:
|
一次做对，真牛！
+5奖励规则>
- 提示1：PHA+55Sx5qKv5b2iQUJDROS4re+8jEFE4oilQkPvvIzlj6/lvpfilrNBT0TiiL3ilrNDT0I8L3A+
- 提示2：PHA+5Y+I55SxQUQ9Me+8jEJDPTTvvIzmoLnmja7nm7jkvLzkuInop5LlvaLnmoTpnaLnp6/mr5TnrYnkuo7nm7jkvLzmr5TnmoTlubPmlrnvvIzljbPlj6/msYLlvpfilrNBT0TkuI7ilrNCT0PnmoTpnaLnp6/mr5QuPC9wPg==
- 答案：RA==
PHA+6Kej77ya4oi15qKv5b2iQUJDROS4re+8jEFE4oilQkPvvIw8YnI+4oi04pazQU9E4oi94pazQ09C77yMPGJyPuKItUFEPTHvvIxCQz0077yMPGJyPuWNs0FE77yaQkM9Me+8mjTvvIw8YnI+4oi04pazQU9E5LiO4pazQk9D55qE6Z2i56ev5q+U562J5LqO77yaMe+8mjE2Ljxicj7mlYXpgIlELjwvcD4=
