Trong mặt phẳng tọa độ
, cho
với trọng tâm
. Biết rằng
,
,
. Hỏi tọa độ đỉnh
là cặp số nào?
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20180021605217162497/obj20180021605217162497862357_images/obj20180021605217162497862357_img1.png)
![img2](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20180021605217162497/obj20180021605217162497862357_images/obj20180021605217162497862357_img2.png)
![img3](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20180021605217162497/obj20180021605217162497862357_images/obj20180021605217162497862357_img3.png)
![img4](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20180021605217162497/obj20180021605217162497862357_images/obj20180021605217162497862357_img4.png)
![img5](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20180021605217162497/obj20180021605217162497862357_images/obj20180021605217162497862357_img5.png)
![img6](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20180021605217162497/obj20180021605217162497862357_images/obj20180021605217162497862357_img6.png)
![img7](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20180021605217162497/obj20180021605217162497862357_images/obj20180021605217162497862357_img7.png)
A.
B.
C.
D.
Đáp án và lời giải
Đáp án:B
Lời giải:
Phân tích: Vì là trọng tâm
nên
Vậy
.
Vậy đáp án đúng là B.