giúp tớ với ạ, tớ cần gấppp
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
a: góc BDC=180-60=120 độ
góc BOC=2*góc BAC=120 độ
góc BAD=góc CAD=60/2=30 độ
=>góc BOD=góc COD=60 độ
góc BOD=1/2*góc BOC
=>OD là phân giác của góc BOC
Xét ΔOBD có OB=OD và góc BOD=60 độ
nên ΔOBD đều
=>góc OBD=60 độ
Xét ΔOCD có OD=OC và góc DOC=60 độ
=>ΔOCD đều
=>góc OCD=60 độ
Xét tứ giác BOCD có
góc BOC=góc BDC
góc OBD=góc OCD
OB=OC
=>BOCD là hình thoi
b:
góc IBC+góc ICB=1/2(góc ABC+góc ACB)=1/2*120=60 độ
=>góc BIC=120 độ
góc BOC=góc BIC=120 độ
=>BOIC nội tiếp
![](https://rs.olm.vn/images/avt/0.png?1311)
xy=-11, x<y
x,y nguyên => \(\hept{\begin{cases}x=-11\\y=1\end{cases}}\)
Vậy (x;y)=(-11;1)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
When a tropical storm reaches 120 kilometers per hour, it is called a typhoon
Wearing uniforms encourages students to be proud of being students of their school
the weather was snowy, we couldn't go to work yesterday
put the garbage into the dustbins, we will minimize pollution
so slowly that his students get bored
difficult to find a better solution
When a tropical storm reaches 120 kilometers per hour, it is called a typhoon
Wearing uniforms encourages students to be proud of being students of their school
the weather was snowy, we couldn't go to work yesterday
put the garbage into the dustbins, we will minimize pollution
so slowly that his students get bored
difficult to find a better solution
![](https://rs.olm.vn/images/avt/0.png?1311)
17 surprisingly
18 time-consuming
19 replacing
20 independent
21 qualifications
22 activists
![](https://rs.olm.vn/images/avt/0.png?1311)
The Internet provides us with a rich source of educational materials and courses.
Facebook has become very popular today because it makes communication around the world very easy
on working despite the rain
worked as a fashion designer for 2 years
I would join your family on the trip to your home village
schoolyard should be kept clean
![](https://rs.olm.vn/images/avt/0.png?1311)
Tớ ko giúp đc)): cọu tự tra google đuy,chứ có google để làm j ((:?
a: BH=3,6cm