Sửa đề: Tìm các giá trị nguyên X thỏa mãn

3: \(\frac{-5}{11}<\frac{9}{x}<\frac{-5}{12}\)

=>\(\frac{-45}{99}<\frac{-45}{-5x}<\frac{-45}{108}\)

=>\(\frac{45}{99}>\frac{45}{-5x}>\frac{45}{108}\)

=>99<-5x<108

=>\(-\frac{99}{5}>x>-\frac{108}{5}\)

mà x nguyên

nên x∈{-20;-21}

4: Ta có: \(\frac{-11}{13}<\frac{9}{x}<\frac{-11}{15}\)

=>\(\frac{-99}{117}<\frac{-99}{-11x}<\frac{-99}{135}\)

=>\(\frac{99}{117}>\frac{99}{-11x}>\frac{99}{135}\)

=>117<-11x<135

=>\(-\frac{117}{11}>x>-\frac{135}{11}\)

mà x nguyên

nên x∈{-11;-12}

5: Ta có: \(\frac{-4}{5}<\frac{9}{x}<\frac{-4}{7}\)

=>\(\frac{-36}{45}<\frac{-36}{-4x}<\frac{-36}{28}\)

=>\(\frac{36}{45}>\frac{36}{-4x}>\frac{36}{28}\)

=>45<-4x<28

=>\(-\frac{45}{4}>x>-\frac{28}{4}\)

mà x nguyên

nên x∈∅

-12(x-5)+7(3-x)=5

=>-12x-(-60)+21-7x=5

=>-12x+60+21-7x=5

=>-12x-7x=5-21-60

=>-19x=-76

=>x=(-76):(-19)

=>x=4

- 12.( x - 5 ) + 7.( 3 - x ) = 5

=> - 12x + 60 + 21 - 7x = 5

=> ( - 12x - 7x ) + 60 + 21 = 5

=> - 19x + 81 = 5

=> - 19x = 5 - 81

=> - 19x = - 76

=> x = ( - 76 ) : ( - 19 )

=> x = 4

Vậy x = 4

-12*(x-5)+7*(3-x)=5

<=> -12x+60+21-7x=5

<=> -19x+81=5

<=> -19x= -76

<=> x= 4

Ta có: \(-12.\left(x-5\right)+7.\left(3-x\right)=5\)

\(\Rightarrow-12.x+60+21-7x=5\)

\(\Rightarrow\left(-19\right).x=5-21-60\)

\(\Rightarrow\left(-19\right)x=\left(-76\right)\)

\(\Rightarrow x=4\)

-12(x-5) + 7(3-x) = 5

-12x + 60 + 21 - 7x = 5

-12x - 7x                = 5 + (-60) + (-21)

-12x + (-7x)            =  -76

       -19x               = -76

         19x              = 76

             x              = 76 : 19 

             x              =     4

Vậy x = 4

k mk nha bn

\(-12\left(x-5\right)+7\left(3-x\right)=5\)

     \(-12x+60+21-7x=5\)

                          \(-19x+81=5\)

                                     \(-19x=5-81\)

                                     \(-19x=-76\)

                                              \(x=4\)

Vậy \(x=4\)

-12.(x-5)+7.(3-x)=5

<=> -12x+60+21-7x=5

<=>-12x-7x=5-60-21

<=>-19x=-76

<=>x=4

-12x+60+21-7x=5

-19x+81=5

-19x=-76

x=4

Ủng hộ mk nha

À, mình xin lỗi, mk tìm ra đáp án rùi =4

- 12.( x - 5 ) + 7.( 3 - x ) = 5

=> - 12x + 60 + 21 - 7x = 5

=> ( - 12x - 7x ) + 60 + 21 = 5

=> - 19x + 81 = 5

=> - 19x = 5 - 81

=> - 19x = - 76

=> x = ( - 76 ) : ( - 19 )

=> x = 4

Vậy x = 4

- 12( x - 5 ) + 7( 3 - x ) = 5

( x - 5 ) . ( 3 - x ) = - 12 + 7 + 5

x - 8 = - 12 + 7 + 5

x - 8 = - 5 + 5

x - 8 = 0

     x = 0 + 8

     x = 8

Nếu mà mình sai thì bạn đừng kêu nhé