Bài 34:

a: =>x+28=0

=>x=-28

b: =>27-x=0 hoặc x+9=0

=>x=27 hoặc x=-9

c: =>x(x-43)=0

=>x=0 hoặc x=43

Bài 1: 

a: 4/9=4/9

5/3=15/9

b: 3/14=-18/84

-5/6=-70/84

c: -2/25=-14/175

-3/35=-15/175

d: -7/20=-35/100

-11/25=-44/100

e: -25/75=-1/3=-5/15

-12/30=-2/5=-6/15

Câu 3: 

a: Ta có: \(2x\left(3x-1\right)-\left(x-3\right)\left(6x+2\right)\)

\(=6x^2-2x-6x^2-2x+18x+6\)

=14x+6

b: Ta có: \(2x\left(x+7\right)-3x\left(x+1\right)\)

\(=2x^2+14x-3x^2-3x\)

\(=-x^2+11x\)

Câu 2: 

a: Ta có: \(\left(-8x^5+12x^3-16x^2\right):4x^2\)

\(=-8x^5:4x^2+12x^3:4x^2-16x^2:4x^2\)

\(=-2x^3+3x-4\)

b: Ta có: \(\left(12x^3y^3-18x^2y+9xy^2\right):6xy\)

\(=12x^3y^3:6xy-18x^2y:6xy+9xy^2:6xy\)

\(=2x^2y^2-3x+\dfrac{3}{2}y\)

c: Ta có: \(\dfrac{x^3-11x^2+27x-9}{x-3}\)

\(=\dfrac{x^3-3x^2-8x^2+24x+3x-9}{x-3}\)

\(=x^2-8x+3\)

d: Ta có: \(\dfrac{6x^4-13x^3+7x^2-x-5}{3x+1}\)

\(=\dfrac{6x^4+2x^3-15x^3-5x^2+12x^2+4x-5x-\dfrac{5}{3}-\dfrac{10}{3}}{3x+1}\)

\(=2x^3-5x^2+4x-\dfrac{5}{3}-\dfrac{\dfrac{10}{3}}{3x+1}\)

Các bạn chỉ cần giúp mik câu c ạ

\(C=\dfrac{x^3}{x^2-4}-\dfrac{x}{x-2}+\dfrac{2}{x+2}\)

\(=\dfrac{x^3-x\left(x+2\right)+2\left(x-2\right)}{x^2-4}\)

\(=\dfrac{x^3-x^2-2x+2x-4}{x^2-4}\)

\(=\dfrac{x^3-x^2-4}{x^2-4}\)

đề đâu bạn

\(\Rightarrow x+3\ge4\\ \Rightarrow x\ge1\)

Đề bài thấy hơi sao sao ấy

đề dúng ấy

b: Các cặp góc so le trong là: \(\hat{P_4};\hat{Q_2}\) ; \(\hat{P_3};\hat{Q_1}\)

Các cặp góc đồng vị là: \(\hat{P_1};\hat{Q_1}\) ; \(\hat{P_2};\hat{Q_2}\) ; \(\hat{P_3};\hat{Q_3}\) ; \(\hat{P_4};\hat{Q_4}\)

Các cặp góc trong cùng phía là: \(\hat{P_4};\hat{Q_1}\) ; \(\hat{P_3};\hat{Q_2}\)

c: Ta có: \(\hat{P_1}+\hat{P_2}=180^0\) (hai góc kề bù)

=>\(\hat{P_2}=180^0-30^0=150^0\)

Ta có: \(\hat{P_1}=\hat{P_3}\) (hai góc đối đỉnh)

mà \(\hat{P_1}=30^0\)

nên \(\hat{P_3}=30^0\)

Ta có: \(\hat{P_2}=\hat{P_4}\) (hai góc đối đỉnh)

mà \(\hat{P_2}=150^0\)

nên \(\hat{P_4}=150^0\)

Ta có: \(\hat{Q_2}+\hat{Q_1}=180^0\) (hai góc kề bù)

=>\(\hat{Q_2}=180^0-30^0=150^0\)

Ta có: \(\hat{Q_1}=\hat{Q_3}\) (hai góc đối đỉnh)

mà \(\hat{Q_1}=30^0\)

nên \(\hat{Q_3}=30^0\)

Ta có: \(\hat{Q_2}=\hat{Q_4}\) (hai góc đối đỉnh)

mà \(\hat{Q_2}=150^0\)

nên \(\hat{Q_4}=150^0\)

1. D => bỏ

2. C

3. C

4. A => the

5. A

6. C =>  next

7. C => taught

8. C => the most

9. D => from

10. B => would

II

1. I wish I would become a singer.

2.  She used to walk to school when she was a child.

3. If I were you, I would learn Chinese

4. The man who I met yesterday was my uncle

5. The trees are watered by me everyday