16 km${}^2$ 55 m${}^2$ = ................... hm${}^2$

Một người đi từ a đến b với vận tốc 30km/h.Lúc về ng đó đi với vận tốc 40km/h. Tính quảng đường ab biết thời gian về ít hơn thời gian đi 30

Tìm x, biết:
a) 3x - 1/4 = 7/5
b) 2x - 3/4 = 1/2
c) 1 + 3x = -5
d) 5/8 + 3/8 x = 9/2
e) 1/2 x - 1/3 = 4/9
f) 4/5 x - 19/5 = -3/5
g) 1,5 x - 7/3 x = 1,5 - 2/3
h) 18/5 - 5/4 x = -1/6
i) 3/5 x - 2/7 = 4/5
j) 2/3 + 7/4 : x = 5/6
k) 2/3 + 1/3 : x = 3/5
l) 5/7 : x - 2/5 = 1/3
m) x : 16/7 + 1/8 = 4/3
n) 1/3 + x : 1/3 = 1

1. Daniel was arrested after he ..... (escape ) from prison

2. When Kathy (meet ) ...... Jonathan, he .... (join ) the Navy.

3. Before they (arrive ) ..... at the airport, they ..... (pay) the taxi driver.

4. When I (arrive ) ...... at the cinema, the film... (start ).

1. My uncle (move) .... to Da Lat in 2005

2. It was the most exciting flim I .... (ever see )

Cho $∆\mathrm{ABC}$, $\angle \mathrm{A}=90°$, đường cao AH; BC=8cm, BH=2cm.

a) Tính AB, AC, AH

b) Trên AC lấy K, gọi D là hình chiếu của A trên BC. C/m: BD.BK=BC

$(\surd x+2)/(2-\surd x)+\surd x/(\surd x+2)-(4x+2\surd x-4)/(x-4) :(-2)/(2-\surd x)+(3+\surd x)/(2\surd x-x)$

${(ab-1)}^2+{(a+b)}^2$

 Chuyển vế ,rút gọn rồi tìm x

a)2x . (x-5) =26+2x ^2

b) (3x-7) .(3-4x)+ 5x=6x(1-2x)

Complete the following sentences using present simple tense (positive/negative/question
forms).
1. Andrea often __________________ (visit) me.
2. Many people __________________ (not like) to be ruled.
3. Selena usually __________________ (prefer) tea.
4. I sometimes __________________ (forget) to take the trash out.
5. My father usually __________________ (wake up) at around 7 o'clock.
6. What time __________________ (the train / arrive) in the morning?
7. __________________ (your class / start) at 8 o’clock?
8. Which one __________________ (you / like) to wear?
9. Thomas occasionally __________________ (invite) me to dinner.
10. I __________________ (be) proud of my family.

giúp em voii ạ em camon nhieu ạ