I/ 2B 3C 

II/ 11D 12D 14C 17C 20D

III/ 24C 

Các câu còn lại bạn làm đúng rồi nha

1 to work by car every morning

2 there 25 students in your class

3 quater past seven

4 is to the left of the drug store

5 small classroom

6 your school have

7 longer than the red river

1. to work by car every morning

2 .there 25 students in your class

3 .quater past seven

4 .is to the left of the drug store

5. small classroom

6 .your school have

7 .longer than the red river

a)\(\dfrac{87}{5}\)

b)\(6\)

c)\(\dfrac{224}{3}\)

d)\(\dfrac{31}{4}\)

Trình bày ra giúp mk ak

a)    2x²y(x²+xy-3y²)

= 2x⁴y + 2x³y² - 6x²y³

b)    (2x+1)(x-1)

= 2x²   -  2x  +  x -1

= 2x² -x -1

c)    (3xy²+6x²y-9xy):3xy

=  y + 2x - 3

d)   \(\dfrac{2x+7}{x+1}+\dfrac{x-4}{x+1}\)

= \(\dfrac{2x+7+x-4}{x+1}\)

= \(\dfrac{3x+3}{x+1}\)

= \(\dfrac{3\left(x+1\right)}{x+1}\)= 3

e)  \(\dfrac{\left(x+2\right)^2}{x-1}:\dfrac{x+2}{3x-3}\)

= \(\dfrac{\left(x+2\right)^2}{x-1}.\dfrac{3\left(x-1\right)}{x+2}\)

= 3(x+2) = 3x+6

f)  \(\left(\dfrac{x^2+2x+2}{x+2}-\dfrac{1}{x+2}\right):\dfrac{x-1}{x+2}\)

= \(\left(\dfrac{x^2+2x+2-1}{x+2}\right):\dfrac{x-1}{x+2}\)

= \(\dfrac{x^2+2x+1}{x+2}.\dfrac{x+2}{x-1}\)

= \(\dfrac{\left(x+1\right)^2}{x-1}\)

còn câu f giúp mik với