题目内容
如图,在梯形ABCD中,AD∥BC,对角线AC、BD交于点O,BE∥CD交CA延长线于点E.
求证:OC2=OA•OE.
求证:OC2=OA•OE.
证明:∵AD∥BC,∴
=
,
又∵BE∥CD,∴
=
,
∴
=
,
∴OC2=OA•OE.
OC |
OA |
OB |
OD |
又∵BE∥CD,∴
OE |
OC |
OB |
OD |
∴
OC |
OA |
OE |
OC |
∴OC2=OA•OE.
练习册系列答案
相关题目