giúp mình nha

a/ \(\left|2x-1,6\right|-2,3=1,4\)

\(\Leftrightarrow\left|2x-1,6\right|=3,7\)

\(\Leftrightarrow\left[{}\begin{matrix}2x-1,6=3,7\\2x-1,6=-3,7\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}2x=5,3\\2x=-2,1\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=2,65\\x=-1,05\end{matrix}\right.\)

Vậy ....

b/ \(5,4-\left|3x-1,2\right|=5,5\)

\(\Leftrightarrow\left|3x-1,2\right|=-0,1\)

Mà \(\left|3x-1,2\right|\ge0\)

\(\Leftrightarrow x\in\varnothing\)

c/ \(\left|x+1,3\right|+\left|x+2,4\right|=4x\)

Mà \(\left\{{}\begin{matrix}\left|x+1,3\right|\ge0\\\left|x+2,4\right|\ge0\end{matrix}\right.\) \(\Leftrightarrow4x\ge0\)

\(\Leftrightarrow x+1,3+x+2,4=4x\)

\(\Leftrightarrow2x+3,7=4x\)

\(\Leftrightarrow3,7=4x-2x\)

\(\Leftrightarrow2x=3,7\)

\(\Leftrightarrow x=1,85\)

Vậy ....

d/ \(\left|x-1,2\right|+\left|2,5-x\right|=0\)

Mà \(\left\{{}\begin{matrix}\left|x-1,2\right|\ge0\\\left|2,5-x\right|\ge0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}\left|x-1,2\right|=0\\\left|2,5-x\right|=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x-1,2=0\\2,5-x=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=1,2\\x=2,5\end{matrix}\right.\) (loại)

Vậy ..

a, \(\left|2x-1,6\right|-2,3=1,4\)

\(\Rightarrow\left|2x-1,6\right|=3,7\)

\(\Leftrightarrow\left[{}\begin{matrix}2x-1,6=3,7\\2x-1,6=-3,7\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2,65\\x=-1,05\end{matrix}\right.\)

b,\(5,4-\left|3x-1,2\right|=5,5\)

\(\Rightarrow\left|3x-1,2\right|=-0,1\) (vô lí)

Vì \(\left|x\right|\ge0\) mà \(\left|3x-1,2\right|< 0\)

Vậy, không có giá trị của x thỏa mãn.

c, \(\left|x+1,3\right|+\left|x+2,4\right|=4x\)

\(\Rightarrow\left\{{}\begin{matrix}\left|x+1,3\right|\ge0\\\left|x+2,4\right|\ge0\end{matrix}\right.\Leftrightarrow4x\ge0\)

\(\Leftrightarrow x+1,3+x+2,4=4x\)

\(\Leftrightarrow x+x+1,3+2,4=4x\)

\(\Leftrightarrow2x+3,7=4x\)

\(\Leftrightarrow2x-4x=-3,7\)

\(\Leftrightarrow-2x=-3,7\)

\(\Leftrightarrow x=\dfrac{3,7}{2}\)

d, \(\left|x-1,2\right|+\left|2,5-x\right|=0\)

\(\Rightarrow\left\{{}\begin{matrix}\left|x-1,2\right|\ge0\\\left|2,5-x\right|\ge0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}\left|x-1,2\right|=0\\\left|2,5-x\right|=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x-1,2=0\\2,5-x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1,2\\x=2,5\end{matrix}\right.\)

\(x\times1,2+x\times3,4+x\times5,4=7,8\)

\(x\times\left(1,2+3,4+5,4\right)=7,8\)

\(x\times10=7,8\)

\(x=7,8:10\)

\(x=0,78\)

x = 0,78

Xx1,2+Xx3,4+Xx5,4=7,8

<=>Xx(1,2+3,4+5,4)=7,8

<=>Xx10=7,8

<=>X=7,8:10=0,78

a) 2,05 x 1,3 + 2,05 x 1,7 = 2,05 x ( 1,3 + 1,7)

                                         =2,05 x 3

                                         = 6,15

b) = 1,2 x (12,5 - 2,5)

    =1,2 x 10

=12

(1,25 - 0,25 x 5) x (1,1 x 1,2 x 1,3 x 1,4 x 1,5)

= (1,25 - 1,25) x (1,1 x 1,2 x 1,3 x 1,4 x 1,5)

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

= 0

x:1,2+x:1,3=250

x: (1,2+1,3)=250

x: 2,5=250

x=250x2,5

x=625

Vậy x= 625

thank you bạn nhiều nha

425,3+x=315,6×12

425,3+x=3787,2

x=3787,2-425,3

x=3361,9

vậy x=3361,9

136,5-x=5,4:1,2

136,5-x=4,5

x=136,5-4,5

x=132

vậy x=132

a)\(425,3+x=315,6×12\)

\(425,3+x=3781,2\)

\(x=3781,2-425,3\)

\(x=3355,9\)

b)\(136,5-x=5,4\div1,2\)

\(\frac{273}{2}-x=\frac{27}{5}+\frac{6}{5}\)

\(\frac{273}{2}-x=\frac{33}{5}\)

\(136,5-x=6,6\)

\(x=136,5-6,6\)

\(x=129,9\)

5,4 x 1,2 - 1,06 x 4 + 15,2 x 2,5 = 40,24

8,3 x (6,25 - 1,75) :  = 37,35

tRẢ LWOFI :....................................................

6,48 - 4,24 + 38

= 2,24 + 38

= 40,24

8,3 x 4,5 : 0,25

= 8,3 x 18

= 149,4

Hk tốt,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

k nhé

8,3 x (6,25 - 1,75) : 0,25 = 149,4

= 1.65 nha

k minh di