I like living in the countryside for a number of reason.The air is fresh and the environment is peaceful which helps me feel relaxed and comfortable.I aslo enjoy the natural beauty of the countryside with is picturesque views of vast green fields and rolling hill.The community is another great as pect,people are friendly and always willing to help each other.Finally the countryside is a sade is a safer place with less traffic and pollution. These factors make life in the countryside healthy and enjoyable

a)Góc A =30 độ,góc B=60 độ,góc C=90 độ/b)BC<AC<AB

a)k=-0,8. b)y=-0,8x .c)khi x=-10thì y=8 và x=2 thì y= -1,6