Trả lời dùm mình với,mình tick cho =(

1. \(x-\left(-12,6\right)=8,7+6,3\) 

\(\Rightarrow x=8,7+6,3+\left(-12,6\right)=2,4\)

2. \(x-5,67x+3,42x=16,75\) 

\(\Rightarrow x\left(1-5,67+3,42\right)=16,75\)

\(\Rightarrow x.\left(-1,25\right)=16,75\)

\(\Rightarrow x=\dfrac{16,75}{-1,25}=-13,4\)

3. \(60\) 

4. \(1000\)

5. \(883000\)

6. \(8\)

7. \(10\)

8. \(1,3\)

9. \(1,46\)

10. \(61\)

11. \(1,4\)

12. \(4,8\)

`a)19,75+6,3=34,25-x:0,4`

`x:0,4=34,25-19,75-6,3`

`x:0,4=8,2`

`x=8,2xx0,4=3,28`

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`b)20,2xx4,3=x xx12,5-88,64`

`x xx12,5=20,2xx4,3+88,64`

`x xx12,5=86,86+88,64=175,5`

`x=175,5:12,5`

`x=14,04`

a: 34,25-x:0,4=19,75+6,3

=>x:0,4=8,2

hay x=3,28

b: =>12,5x-88,64=20,2x4,3

=>12,5x=175,5

hay x=14,04

a/ x+65,27=72,6

    x=72,6-65,27

     x=7,33

b/x-43,502=21,73

            x=21,73+43,502

              x=65,232

c/x.6,3=187

           x=187:6,3

           x=29,682....

d/ 1602:x=7,2

           x=1602:7,2

           x=222,5

\(X+65,27=72,6\\ X=72,6-65,27=7,33\\ ---\\ X-43,502=21,73\\ X=21,73+43,502=65,232\\ ---\\ X.6,3=187\\ X=\dfrac{187}{6,3}=\dfrac{1870}{63}\\ ---\\ 1602:X=7,2\\ X=1602:7,2=222,5\)

\(x+x\div5=12,6\)

\(x\times\left(1+\frac{1}{5}\right)=12,6\)

\(x\times\frac{6}{5}=12,6\)

\(x=12,6\div\frac{6}{5}=\frac{12,6\times5}{6}\)

\(\Rightarrow x=10,5\)

x + x . \(\frac{1}{5}\)= 12,6

x . ( 1 + 1/5) = 12,6

x . 1,2  = 12,6

x  = 1,05 

= 15,7 x (6,3 + 3,7)

= 15,7 x 10

= 157

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23 + 25 + 27 + 29 + 31 + 33 + 35 +37

= (23 + 37) + (25 + 35) + (27 + 33) + (29 + 31)

= 60 + 60 + 60 + 60

= 60 x 4= 240 

=[(-6,3)+6,3]+5,1

=0+5,1

=5,1

`6,3 + 5,1 + (-6,3)`

`= (-6,3 + 6,3) +5,1`

`= 0 +5,1`

`= 5,1`

\(\left|-x-3,2\right|+5,4=\)\(12,6\)

<=> \(\left|-x-3,2\right|=7,2\)

<=> \(\hept{\begin{cases}-x-3,2=7,2\\-x-3,2=-7,2\end{cases}}\)

<=> \(\hept{\begin{cases}-x=10,4\\-x=-4\end{cases}}\)

<=> \(\hept{\begin{cases}x=10,4\\x=4\end{cases}}\)

B= 0+4,9

B= 4,9

\(B=4,9\)