1, was brushing/rang

2, walked

3, was preparing

e vs ạ

10, Xét tam giác ABC vuông tại A:

             BC^2=AC^2 +AB^2 (ĐL Py-ta-go)

       hay 10^2=6^2 + AB^2

        ⇔  100=36 + AB^2

        ⇔  AB^2= 64

        ⇔  AB=√64=8 (AB>0)

Xét tag ABC vuông tại A có:

       sin∠B= AC/BC=6/10=0,6 ⇒ ∠B = 37 độ

       sin∠C=AB/BC=8/10=0,8 ⇒ ∠C= 53 độ

1, He said that he had a sister, her name was Hoa

2, He asked us not to step on that floor

3, He asked how much meat she had bought

4, He asked her if that book was hers

5, He asked me if that book was mine

Xét tg ABC vuông tại A, đường cao AH:

       AB^2= BH.BC (hệ thức lượng)

     hay 9 = BH. 20

⇒ BH= 0,45

Xét tg ABC vuông tại A, đường cao AH:

       AC^2= CH.BC (hệ thức lượng)

     hay 16= CH.20

⇒ CH= 0,8

31, He wishes his mother was with him

32, That book is not as fascinating as this one

33, Their work have just been finished 

34, Tom said that his mother had given him a book for his birthday

35, I haven't played tennis for three weeks