4(x - 0,5) - 3(x + 1,5) = -x + 2,5

=> 4x - 2 - 3x - 4,5 = -x + 2,5

=>  (4x - 3x) + (-2 - 4,5) = -x + 2,5

=>    x - 6,5 = -x + 2,5

=> x + x = 2,5 + 6,5

=> 2x = 9 => x = \(\dfrac{9}{2}\)

Vậy x = \(\dfrac{9}{2}\)

đây nha bạn

Huhuhuhu ai giúp e vs chứ e sắp thi r ạ :(((((

B.

I.1.A ; 2.C

II.1.A;2.A;3.B;4.D;5.B;6.A

1 A

2 C

3 C

4 C

5 B

5 C

5 B

6 A

C

I

1 - C

2 - D

3 - B

4 - A

II

1 People of ethnic minorities 

2 In March of every year

3 Money and other things

4 No, they aren't

5 Around all the villages

D

1 play volleyball

2 are 50 teachers and 800 students in my school

3 terrible weather

4 works fewer hours than ,e

II

1 performance

2 cultural

3 seasonal

4 carelessly

I.1.A ; 2.C

II.1.A;2.A;3.B;4.D;5.B;6.A

Tôi còn thức tới 11:45

\(A\left(x\right)+B\left(x\right)=3x^4-4x^3+2x^2-3+8x^4+x^3-9x+\dfrac{2}{5}\)

\(=11x^4-3x^3+2x^2-9x-\dfrac{13}{5}\)

\(A\left(x\right)-B\left(x\right)=3x^4-4x^3+2x^2-3-8x^4-x^3+9x-\dfrac{2}{5}\)

\(=-5x^4-5x^3+2x^2+9x-\dfrac{17}{5}\)

\(B\left(x\right)-A\left(x\right)=8x^4+x^3-9x+\dfrac{2}{5}-3x^4+4x^3-2x^2+3\)

\(=5x^4+5x^3-2x^2-9x+\dfrac{17}{5}\)

\(A\left(x\right)+B\left(x\right)=11x^4-3x^3+2x^2-9x-\dfrac{13}{5}\)

\(A\left(x\right)-B\left(x\right)=-5x^4-5x^3+2x^2+9x-\dfrac{17}{5}\)

\(B\left(x\right)-A\left(x\right)=5x^4+5x^3-2x^2-9x+\dfrac{17}{5}\)

a) Ta có: \(P\left(x\right)=3x^5-2x^4-2x^5-2x^2-x+3x^2+2\)

\(=x^5-2x^4+x^2+2\)

Ta có: \(Q\left(x\right)=x^5+8-5x+3x^3+3x+x^4-4x^5\)

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

b) \(P\left(x\right)+Q\left(x\right)=x^5-2x^4+x^2+2-3x^5+x^4+3x^3-2x+8\)

\(=-2x^5-x^4+3x^3+x^2-2x+10\)

\(P\left(x\right)-Q\left(x\right)=x^5-2x^4+x^2+2+3x^5-x^4-3x^3+2x-8\)

\(=4x^5-3x^4-3x^3+x^2+2x-6\)

\(3,8276< \overline{3,8ab5}< 3,836\)

=>\(276< \overline{ab5}< 360\)

=>\(\left(a,b\right)\in\left\{\left(2;8\right);\left(2;9\right);\left(3;0\right);\left(3;1\right);\left(3;2\right);\left(3;3\right);\left(3;4\right);\left(3;5\right)\right\}\)