1 / 11

# 回顾与思考 - PowerPoint PPT Presentation

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## PowerPoint Slideshow about ' 回顾与思考' - anevay

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

A

D

C

B

(1)菱形是平行四边形，

(2)一组邻边相等．

①菱形是中心对称图形和轴对称图形；

②菱形的四条边都相等；

③菱形的对角相等；

④菱形的对角线互相垂直平分；并且每一条对角线平分一组对角；

E

S菱形＝AB·DE

A

【菱形的面积公式】

S菱形

ABCD=S△ABD+S△BCD= AC×BD

B

D

C

O

E

S菱形=BC. AE

2 菱形的一个内角为120°，且平分这个内角的一条对角线为8厘米，求这个菱形的周长。

3 试说明：菱形对角线交点到各边距离相等．

1.菱形概念

①菱形既是轴对称图形，又是中心对称图形。

②菱形的四条边都相等；

③菱形的对角相等；

④菱形的对角线互相垂直平分；其中每一条对角线平分一组对角；

2.菱形特征

3.菱形与平行四边形的关系

4.菱形的面积

= 对角线的乘积的一半