Đáp án :x = 2 

may tinh dau

sao ko tu tinh

198 - 42 : 6 . x + 16 = 200

=> 214 - 7x = 200

=> 7x = 214 - 200

=> 7x = 14

=> x = 14 : 7

=> x = 2

\(198-42:6\times x+16=200\)

\(198-7\times x=200-16\)

\(198-7\times x=184\)

\(7\times x=198-184\)

\(7\times x=14\)

\(x=14:7\)

\(x=2\)

Hok tốt

\(198-42:6\cdot x+16=200\)

\(198-7\cdot x+16=200\)

\(198-7\cdot x=200-16\)

\(198-7\cdot x=184\)

\(7\cdot x=198-184\)

\(7\cdot x=14\)

\(x=14:7\)

\(x=2\)

~~~~Hok tốt ! =^.^=~~~~

198 - 42 : 6x + 16 = 200

=> -42 : 6x = 200 - 198 - 16

=> -42 : 6x = -14

=> 6x = -42 : (-14)

=> 6x = 3

=> x = 1/2

198+ 42 : 6 x Y = 200

198    +   7  x   y  = 200

198 +   y       =  200 x 7

198   +  y    = 1400

             y  =  1400 - 

198+ 42 : 6 x Y = 200

198    +   7  x   y  = 200

198 +   y       =  200 x 7

198   +  y    = 1400

            y = 1400   -   198  

             y   =  1202

TL

1202 nha bn cute phô mai que

HT

TL ;

198 + 42 : 6 x y = 200

198 + 7 x y = 200

198 + y = 200 x 7

198 + y = 1400

y = 1400 - 198

y = 1202

42-2(x+16) +12 :2=6(x-1)+ (-4)^3 :16

42- 2x- 32 +6 = 6x - 6 - 64: 16

(42 - 32 +6) - 2x = 6x - 6 - 4

16 = 2x = 6x- 10

16+10= 2x+6x

26= 8x 

x= 26/8

x= 13/4

42-2(x+16)+12:2=6(x-1)+(-4)³:16

42-2(x+16)+6=6(x-1)-64:16

42-2x-32+6=6x-6-4

-2x+16=6x-10

6x+2x=16+10

8x=26

x=3,25

2: Tìm x

a) Ta có: x+25=40

nên x=40-25=15

Vậy: x=15

b) Ta có: 198-(x+4)=120

\(\Leftrightarrow x+4=198-120=78\)

hay x=78-4=74

Vậy: x=74

c) Ta có: \(\left(2x-7\right)\cdot3=125\)

\(\Leftrightarrow2x-7=\dfrac{125}{3}\)

\(\Leftrightarrow2x=\dfrac{125}{3}+7=\dfrac{125}{3}+\dfrac{21}{3}=\dfrac{146}{3}\)

\(\Leftrightarrow x=\dfrac{146}{3}:2=\dfrac{146}{6}=\dfrac{73}{3}\)

Vậy: \(x=\dfrac{73}{3}\)

d) Ta có: \(x+16⋮x+1\)

\(\Leftrightarrow x+1+15⋮x+1\)

mà \(x+1⋮x+1\)

nên \(15⋮x+1\)

\(\Leftrightarrow x+1\inƯ\left(15\right)\)

\(\Leftrightarrow x+1\in\left\{1;-1;3;-3;5;-5;15;-15\right\}\)

hay \(x\in\left\{0;-2;2;-4;4;-6;14;-16\right\}\)

Vậy: \(x\in\left\{0;-2;2;-4;4;-6;14;-16\right\}\)

\(a,x+25=40\\ \Rightarrow x=40-25\\ \Rightarrow x=15\\ b,198-\left(x+4\right)=120\\ \Rightarrow-\left(x+4\right)=120-198\\ \Rightarrow-\left(x+4\right)=-78\\ \Rightarrow x+4=78\\ \Rightarrow x=78-4\\ \Rightarrow x=74\\ c,\left(2x-7\right).3=125\\ \Rightarrow2x-7=\dfrac{125}{3}\\ \Rightarrow2x=\dfrac{125}{3}+7\\ \Rightarrow2x=\dfrac{146}{3}\\ \Rightarrow x=\dfrac{146}{3}:2\Rightarrow x=\dfrac{73}{3}\\ d,\left(x+16\right)⋮\left(x+1\right)\\ \Rightarrow\left[\left(x+1\right)+15\right]⋮\left(x+1\right)\\ mà:\left(x+1\right)⋮\left(x+1\right)\\ \Rightarrow15⋮\left(x+1\right)\\ \Rightarrow\left(x+1\right)\inƯ\left(15\right)\\ \Rightarrow\left(x+1\right)\in\left\{-15;-1;1;15\right\}\\ \Rightarrow x\in\left\{-16;-2;0;14\right\}\)

Tự kết luận nhé bạn

1 , 10

2 , 8

3 , 5

4 , 2

5 , 1

6 ,

1/ `|x|=10<=> x=\pm 10`

2/ `|x-8|=0<=>x-8=0<=>x=8`

3/ `7+|x|=12<=>|x|=5<=>x=\pm 5`

4/ `|x+1|=3`

$\Leftrightarrow\left[\begin{array}{1}x+1=3\\x+1=-3\end{array}\right.\\\Leftrightarrow\left[\begin{array}{1}x=3\\x=-4\end{array}\right.$

5/ `15-x=16-(14-42)`

`<=>15-x=16+28`

`<=>15-x=44`

`<=>x=-29`

6/ `210-(x-12)=168`

`<=>210-x+12=168`

`<=>222-x=168`

`<=>x=54`

1.

\(\left|x\right|=10\Leftrightarrow x=\pm10\)

2.

\(\left|x-8\right|=0\Leftrightarrow x-8=0\Leftrightarrow x=8\)

3.

\(7+\left|x\right|=12\Leftrightarrow\left|x\right|=5\Leftrightarrow x=\pm5\)

Hình như đề sai thì phải pn xem kĩ lại nkoa!