Bài 2: Cho ∆ABC có AB AC = , M là trung điểm của BC . Trên tia đối của tia MA lấy điểm D sao cho MA = MD . a) Chứng minh : ∆ ABM =∆ DCM .
b) AB // DC
c) AM ⊥ MC
d) Tìm điều kiện ∆ABC để góc ADC =30 °

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations:

12

step-by-step explanation:

a triangle's   full angle is 180 degrees so 180 - 156 = 24. 24/2=12