mà z đâu ra thế

x=y=0

100 điểm 10

vừa đăng mà

sửa lỗi sai:
1. Turn off the TV when you are not watching.
2. Biogas will be used for fuel in homes and for transport.
3. He intends to marry tich someones.
4. The wind turn turbines to make electricity.
5. Natural gas is limited and it is harmful at the enviroment.
6. A network of wind turbines will install to generate electricity.
7. Solar energy is renewable. It is clean and safe.
8. I recycle the production I use and I go everywhere by bike.
9. This time next year we will be having a free solar shower.
10. I d'like to talk to you about renewable and non-renewable energy.
11. He feels like paying a visit to the capital of Viet Nam.
12. Please give this present for my family.

Xét \(\Delta MAB\) và \(\Delta MDC\) có :

\(BM=MC\) ( AM là đường trung tuyến của BC )

\(AM=MD\left(gt\right)\)

\(\widehat{M_1}=\widehat{M_2}\) ( đối đỉnh )

\(Do\) đó \(\Delta MAB=\Delta MDC\) \(\left(c-g-c\right)\)

\(\Rightarrow AB=CD\) ( cạnh tương ứng )

b) Xét \(\Delta ACD\) có :

\(AC+CD>AD\) ( bất đẳng thức tam giác )

\(\Rightarrow AC+AB>AM+MD\) ( do \(AB=CD\))

\(\Rightarrow AB+AC>2AM\) (\(AM=MD\) ) đpcm