cho tam giac ABC . tren BC lay BM =2/3 BC.
a, so sanh dien tich tam giac ABM va AMC; dien tich tam giac AMC va ABC
b, tren AC lay N la trung diem. so sanh dien tich tam giac ANM va dien tich tam giac ABC
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) M điểm giữa của BC nên CM = MB
Tam giác ABM và tam giác ACM có : đáy CM = MB, chung đường cao tương ứng với đáy.
Nên S(ABM) = S(ACM)
b) S(ABC) = S(ABM) + S(ACM) mà S(ABM) = S(ACM)
Nên \(S\left(ABM\right)=\frac{1}{2}S\left(ABC\right)\)
1/2 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000% luob
Sr nãy giờ quên mất câu này
A.
Ta có diện tích AMC < diện tích BMC vì AM < BM (gt)
B.
Ta có diện tích BNC < diện tích BMC vì NC < BM
Hình bạn tự vẽ vì cũng dễ mà