题目内容
如图,在四边形ABCD中,∠B=135°,∠C=120°,AB=2
,BC=4-2
,CD=4
,则AD边的长为______.

3 |
2 |
2 |

如图,过点A,D分别作AE,DF垂直于直线BC,垂足分别为E,F.
∵∠B=135°,
∴∠ABE=45°,
∴BE=AE=
,
∵∠C=120°,
∴∠DCF=60°,
∵CD=4
,
∴CF=2
,
∴DF=2
,
∴EF=4+
.
过点A作AG⊥DF,垂足为G.在Rt△ADG中,根据勾股定理得
AD=
=
=2+2
.
故答案为:2+2
.

∵∠B=135°,
∴∠ABE=45°,
∴BE=AE=
6 |
∵∠C=120°,
∴∠DCF=60°,
∵CD=4
2 |
∴CF=2
2 |
∴DF=2
6 |
∴EF=4+
6 |
过点A作AG⊥DF,垂足为G.在Rt△ADG中,根据勾股定理得
AD=
(4+
|
(2+
|
6 |
故答案为:2+2
6 |


练习册系列答案
相关题目