a: \(x-43=\left(35-x\right)-48\)

=>\(x-43=35-x-48\)

=>\(x-43=-x-13\)

=>\(x+x=-13+43\)

=>2x=30

=>x=30/2=15

b: \(305-x+14=48+\left(x-23\right)\)

=>\(319-x=48+x-23=25+x\)

=>\(x+25=319-x\)

=>\(x+x=319-25\)

=>\(2x=294\)

=>\(x=\dfrac{294}{2}=147\)

c: \(-\left(-x-6+85\right)=\left(x+51\right)-54\)

=>\(-\left(-x+79\right)=x+51-54\)

=>x-79=x-3

=>-79=-3(vô lý)

=>\(x\in\varnothing\)

d: \(-\left(35-x\right)-\left(37-x\right)=33-x\)

=>\(-35+x-37+x=33-x\)

=>2x-72=-x+33

=>\(2x+x=33+72\)

=>3x=105

=>\(x=\dfrac{105}{3}=35\)

1,x-43=(35-x)-48

=>x-43=35-x-48

=>x+x=35-48+43

=>2x=30

=>x=15

Vậy x=15

2,305-x+14=48+(x-23)

=>305-x+14=48+x-23

=>305+14+23-48=x+x

=>294=2x

=>x=294:2

=>x=147

3,-(x-6+85)=(x+51)-54

=>-x+6-85=x+51-54

=>6-85-51+54=x+x

=>-76=2x

=>x=(-76):2

=>x=-38

4,-(35-x)-(37-x)=33-x

=>-35+x-37+x=33-x

=>-35+(-37)+(-33)=-x-x-x

=>-105=-3x

=>x=(-105):(-3)

=>x=35

5,13-\(|x|=|-4|\)

=>13-\(|x|\)=4

=>13-4=\(|x|\)

=>9=\(|x|\)

=>x=9 hoặc x=-9

5) 13 - |x| = |-4|

=> 13 - |x| = 4

|x| = 13-4 = 9

Vậy x=9 hoặc x=-9

4) - (35-x) - (37-x) = 33-x

<=>-35 + x - 37 + x = 33-x

<=> -35 - 37 + x + x = 33-x

-72 + 2x = 33 - x

Theo quy tắc chuyển vế, ta có

-72 - 33 = - 2x + x

-105 = - (2x+x)

-105 = -3x

=> x = (-105) : (-3) = 35

Vậy x=35

Mk chỉ làm đc hai câu thôi. Mk có việc nên ko thể làm tiếp đc cho bạn nữa nha...

a) Ta có: x-43=(35-x)-48

⇔x-43=35-x-48

⇔x-43=-x-13

⇔x-43+x+13=0

⇔2x-30=0

⇔2(x-15)=0

mà 2≠0

nên x-15=0

hay x=15

b) Ta có: 305-x+14=48+(x-23)

⇔319-x=48+x-23

⇔319-x=x+25

⇔319-x-x-25=0

⇔-2x+294=0

⇔-2x=-294

hay x=147

Vậy: x=147

c) Ta có: -(x-6+85)=(x+51)-54

⇔-x+6-85=x+51-54

⇔-x-79=x-3

⇔-x-79-x+3=0

⇔-2x-76=0

⇔-2x=76

hay x=-38

Vậy: x=-38

d) Ta có: -(35-x)-(37-x)=33-x

⇔-35+x-37+x-33+x=0

⇔3x-105=0

⇔3(x-35)=0

mà 3≠0

nên x-35=0

hay x=35

Vậy: x=35

e) Ta có: 13-|x|=|-4|

⇔13-|x|=4

⇔|x|=9

⇔x∈{9;-9}

Vậy: x∈{9;-9}

f) Ta có: |x|-3+6=16

⇔|x|+3=16

⇔|x|=13

hay x∈{-13;13}

Vậy: x∈{-13;13}

g) Ta có: 35-|2x-1|=14

⇔|2x-1|=21

⇔\(\left[{}\begin{matrix}2x-1=21\\2x-1=-21\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=22\\2x=-20\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=11\\x=-10\end{matrix}\right.\)

Vậy: x∈{11;-10}

h) Ta có: |3x-2|+5=9-x

⇔|3x-2|+5-9+x=0

⇔|3x-2|-4+x=0

⇔|3x-2|=0-(-4+x)

⇔|3x-2|=4-x

⇔\(\left[{}\begin{matrix}3x-2=4-x\\3x-2=x-4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}3x-2-4+x=0\\3x-2-x+4=0\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}4x-6=0\\2x+2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}4x=6\\2x=-2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\frac{3}{2}\left(ktm\right)\\x=-1\left(tm\right)\end{matrix}\right.\)

Vậy: x=-1

1, ( - 12 ) - ( 13 - x ) = - 15 - ( - 17 )

=> - 12  - 13 + x = - 15 + 17

=> - 25 + x = 2

=> x = 2 + 25 

=> x = 27 

2, 305 - x + 14 = 48 + ( x - 23 )

=> 305 - x + 14 = 48 + x - 23

=> x + x = 305 + 14 - 48 + 23

=> 2x = 294

=> x = 147

3, - ( x - 6 + 85 ) = ( x + 51 ) - 54

=> - x + 6 - 85 = x + 51 - 54

=> x + x = 6 - 85 - 51 + 54

=> 2x = - 76

=> x = - 38

4, - ( 35 - x ) - ( 37 - x ) = 33 - x

=> - 35 + x - 37 + x = 33 - x

=> x + x + x = 33 + 35 + 37

=> 3x = 105

=> x = 35

1.    x=-27

2.   x=147

3.   x=41

4    x=35 

Câu 1

(-12)-(3-x)=-15-(-17)

-12-3+x=-15+17

-15+x=2

x=17

Câu 2

305-x+14=48+(x-23)

319-x=25+x

2x=294

x=147

các câu còn lại giông nên mk ch đáp án

3,-38

4,35

Ai lm hộ mk nha

Nhiều quá bạn ơi

1.\(x-43=\left(35-x\right)-48\)

\(\Rightarrow x-43=35-x-48\)

\(\Rightarrow2x=35+43-48\)

\(\Rightarrow2x=30\)

\(\Rightarrow x=15\)

2.\(305-x+14=48+\left(x-23\right)\)

\(\Rightarrow305-x+14=48+x-23\)

\(\Rightarrow305+14=48+x+x-23\)

\(\Rightarrow2x+25=319\)

\(\Rightarrow2x=294\)

\(\Rightarrow x=147\)

3.\(-\left(x-6+85\right)=\left(x+51\right)-54\)

\(\Rightarrow-x+6-85=x+51-54\)

\(\Rightarrow6-85=x+x+51-54\)

\(\Rightarrow2x-3=-79\)

\(\Rightarrow2x=-76\)

\(\Rightarrow x=-38\)

4.\(-\left(35-x\right)-\left(37-x\right)=33-x\)

\(\Rightarrow-35+x-37+x=33-x\)

\(\Rightarrow2x-72=33-x\)

\(\Rightarrow3x=105\)

\(\Rightarrow x=35\)

5.\(13-\left|x\right|=\left|-4\right|\)

\(\Rightarrow13-\left|x\right|=4\)

\(\Leftrightarrow\left[{}\begin{matrix}13-x=4\\13+x=4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=9\\x=-9\end{matrix}\right.\)

dài quá à :(

1) x - 43 = (35 - x) - 48

=> x + x = 35 - 48 + 43

=> x + x = 30

=> x = 30 : 2

=> x = 15

2) 305 - x + 14 = 48 + (x + 23)

=> 305 - x + 14 = 48 + x + 23

=> -x - x = 48 + 23 - 14 - 305

=> -x - x = -248

=> -x = -248 : 2

=> -x = -124

=> x = 124

3) - (x - 6 + 85) = (x + 51) - 54

=> -x + 6 - 85 = x + 51 - 54

=> -x - x = 51 - 54 + 85 - 6

=> -x - x = 76

=> -x = 76 : 2

=> -x = 38

=> x = -38

4) - (35 - x - 37 - x) = 33 - x

=> -35 + x + 37 + x = 33 - x

=> x + x + x = 33 + 35 - 37

=> x + x + x = 31

=> x = 31 : 3

=> x \(=\dfrac{31}{3}\)

Vì x \(\in\) Z nên không có giá trị x nào thỏa mãn trong câu này.

5) 13 - | x | = | -4 |

=> 13 - |x| = 4

=> |x| = 13 - 4

=> |x| = 9

=> \(\left[{}\begin{matrix}x=9\\x=-9\end{matrix}\right.\)

6) | x | - 3 + 6 = 16

=> |x| = 16 - 6 + 3

=> |x| = 13

=> \(\left[{}\begin{matrix}x=13\\x=-13\end{matrix}\right.\)

7) 35 - | 2x - 1 | = 14

=> |2x - 1| = 35 - 14

=> |2x - 1| = 21

=> \(\left[{}\begin{matrix}2x-1=21\\2x-1=-21\end{matrix}\right.=>\left[{}\begin{matrix}2x=21+1\\2x=-21+1\end{matrix}\right.=>\left[{}\begin{matrix}2x=22\\2x=-20\end{matrix}\right.=>\left[{}\begin{matrix}x=22:2\\x=-20:2\end{matrix}\right.=>\left[{}\begin{matrix}x=11\\x=-10\end{matrix}\right.\)

8) | 3x - 2 | + 5 = 9 - x

=> |3x - 2| = 9 - 5 - x

=> |3x - 2| = 4 - x

=> \(\left[{}\begin{matrix}3x-2=4-x\\3x-2=x-4\end{matrix}\right.=>\left[{}\begin{matrix}3x+x=4+2\\3x-x=-4+2\end{matrix}\right.=>\left[{}\begin{matrix}4x=6\\2x=-2\end{matrix}\right.=>\left[{}\begin{matrix}x=6:4\\x=-2:2\end{matrix}\right.=>\left[{}\begin{matrix}x=\dfrac{6}{4}\\x=-1\end{matrix}\right.\)

Vì x \(\in\) Z nên x = -1.

9) x - ( -25 + 7 ) > 12 - ( 15 - 14 )

=> x - (-18) > 12 - 1

=> x + 18 > 11

=> x > 11 - 18

=> x > -7

10) | 17 + ( x - 15 ) | < 4

=> \(\left[{}\begin{matrix}17+\left(x-15\right)< 4\\17+\left(x-15\right)< -4\end{matrix}\right.=>\left[{}\begin{matrix}x-15< 4-17\\x-15< -4-17\end{matrix}\right.=>\left[{}\begin{matrix}x-15< -15\\x-15< -21\end{matrix}\right.=>\left[{}\begin{matrix}x< -15+15\\x< -21+15\end{matrix}\right.=>\left[{}\begin{matrix}x< 0\\x< -6\end{matrix}\right.=>x< -6\)

11) x2 - 5x = 0

=> x . (2 - 5) = 0

=> x . (-3) = 0

=> x = 0 : (-3)

=> x = 0

12) | x-9 | . (-8) = -16

=> |x - 9| = (-16) : (-8)

=> |x - 9| = 3

=> \(\left[{}\begin{matrix}x-9=3\\x-9=-3\end{matrix}\right.=>\left[{}\begin{matrix}x=3+9\\x=-3+9\end{matrix}\right.=>\left[{}\begin{matrix}x=12\\x=6\end{matrix}\right.\)

13) | 4 - 5x | = 24 với x < hoặc = 0

=> \(\left[{}\begin{matrix}4-5x=24\\4-5x=-24\end{matrix}\right.=>\left[{}\begin{matrix}5x=4-24\\5x=4-\left(-24\right)\end{matrix}\right.=>\left[{}\begin{matrix}5x=-20\\5x=28\end{matrix}\right.=>\left[{}\begin{matrix}x=-20:5\\x=28:5\end{matrix}\right.=>\left[{}\begin{matrix}x=-4\\x=\dfrac{28}{5}\end{matrix}\right.\)

Vì x \(\le\) 0 nên x = -4

14) x . ( x - 2 ) > 0

=> \(\left[{}\begin{matrix}\left\{{}\begin{matrix}x>0\\x-2>0\end{matrix}\right.\\\left\{{}\begin{matrix}x< 0\\x-2< 0\end{matrix}\right.\end{matrix}\right.=>\left[{}\begin{matrix}\left\{{}\begin{matrix}x>0\\x>2\end{matrix}\right.\\\left\{{}\begin{matrix}x< 0\\x< 2\end{matrix}\right.\end{matrix}\right.=>\left[{}\begin{matrix}x>2\\x< 2\end{matrix}\right.\)

15) x . ( x - 2 ) < 0

=> \(\left[{}\begin{matrix}\left\{{}\begin{matrix}x< 0\\x-2>0\end{matrix}\right.\\\left\{{}\begin{matrix}x>0\\x-2< 0\end{matrix}\right.\end{matrix}\right.=>\left[{}\begin{matrix}\left\{{}\begin{matrix}x< 0\\x>2\end{matrix}\right.\\\left\{{}\begin{matrix}x>0\\x< 2\end{matrix}\right.\end{matrix}\right.=>\left[{}\begin{matrix}2>x< 0\left(loại\right)\\0< x< 2\left(chọn\right)\end{matrix}\right.=>0< x< 2\)

16) (x-1) . (y+1) = 5

=> \(\left[{}\begin{matrix}x-1=5\\y+1=1\end{matrix}\right.=>\left[{}\begin{matrix}x=5+1\\y=1-1\end{matrix}\right.=>\left[{}\begin{matrix}x=6\\y=0\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x-1=1\\y+1=5\end{matrix}\right.=>\left[{}\begin{matrix}x=1+1\\y=5-1\end{matrix}\right.=>\left[{}\begin{matrix}x=2\\y=4\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x-1=-1\\y+1=-5\end{matrix}\right.=>\left[{}\begin{matrix}x=-1+1\\y=-5-1\end{matrix}\right.=>\left[{}\begin{matrix}x=0\\y=-6\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x-1=-5\\y+1=-1\end{matrix}\right.=>\left[{}\begin{matrix}x=-5+1\\y=-1-1\end{matrix}\right.=>\left[{}\begin{matrix}x=-4\\y=-2\end{matrix}\right.\)

17) x . ( y +2 ) = -8

=> \(\left[{}\begin{matrix}x=1\\y+2=-8\end{matrix}\right.=>\left[{}\begin{matrix}x=1\\y=-8-2\end{matrix}\right.=>\left[{}\begin{matrix}x=1\\y=-10\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x=-1\\y+2=8\end{matrix}\right.=>\left[{}\begin{matrix}x=-1\\y=8-2\end{matrix}\right.=>\left[{}\begin{matrix}x=-1\\y=4\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x=-8\\y+2=1\end{matrix}\right.=>\left[{}\begin{matrix}x=-8\\y=1-2\end{matrix}\right.=>\left[{}\begin{matrix}x=-8\\y=-1\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x=8\\y+2=-1\end{matrix}\right.=>\left[{}\begin{matrix}x=8\\y=-1-2\end{matrix}\right.=>\left[{}\begin{matrix}x=8\\y=-3\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x=2\\y+2=-4\end{matrix}\right.=>\left[{}\begin{matrix}x=2\\y=-4-2\end{matrix}\right.=>\left[{}\begin{matrix}x=2\\y=-6\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x=-2\\y+2=4\end{matrix}\right.=>\left[{}\begin{matrix}x=-2\\y=4-2\end{matrix}\right.=>\left[{}\begin{matrix}x=-2\\y=2\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x=4\\y+2=-4\end{matrix}\right.=>\left[{}\begin{matrix}x=4\\y=-4-2\end{matrix}\right.=>\left[{}\begin{matrix}x=4\\y=-6\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}x=-4\\y+2=2\end{matrix}\right.=>\left[{}\begin{matrix}x=-4\\y=2-2\end{matrix}\right.=>\left[{}\begin{matrix}x=-4\\y=0\end{matrix}\right.\)

18) xy - 2x - 2y = 0

=> x . (y - 2) - 2y = 0

=> x . (y - 2) - 2y - 4 = -4

=> x . (y - 2) - 2 . (y - 2) = -4

=> (y - 2) . (x - 2) = -4

=> \(\left[{}\begin{matrix}y-2=1\\x-2=-4\end{matrix}\right.=>\left[{}\begin{matrix}y=1+2\\x=-4+2\end{matrix}\right.=>\left[{}\begin{matrix}y=3\\x=-2\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}y-2=-1\\x-2=4\end{matrix}\right.=>\left[{}\begin{matrix}y=-1+2\\x=4+2\end{matrix}\right.=>\left[{}\begin{matrix}y=1\\x=6\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}y-2=2\\x-2=-2\end{matrix}\right.=>\left[{}\begin{matrix}y=2+2\\x=-2+2\end{matrix}\right.=>\left[{}\begin{matrix}y=4\\x=0\end{matrix}\right.\)

hoặc

=> \(\left[{}\begin{matrix}y-2=-2\\x-2=2\end{matrix}\right.=>\left[{}\begin{matrix}y=-2+2\\x=2+2\end{matrix}\right.=>\left[{}\begin{matrix}y=0\\x=4\end{matrix}\right.\)

19) 2x - 5 \(⋮\) x - 1

=> (2x - 2) - (5 - 2) \(⋮\) x - 1

=> 2(x - 1) - 3 \(⋮\) x - 1

Vì 2(x - 1) \(⋮\) x - 1 nên 3 \(⋮\) x - 1

=> x - 1 \(\in\) Ư(3) = {-3; -1; 1; 3}

=> x \(\in\) {-2; 0; 2; 4}

P/s: Mình không bảo đảm là đúng hết nên câu nào sai thì bạn thông cảm nha~