1/ x²⁰¹⁵ - (-42 - 2x) = 6 + x²⁰¹⁵

=> x²⁰¹⁵ + 42 + 2x = 6 + x²⁰¹⁵

=> x²⁰¹⁵ + 2x - x²⁰¹⁵ = 6 - 42

=> (x²⁰¹⁵ - x²⁰¹⁵) + 2x = 6 - 42

=> 2x = -36

=> x = -36 : 2

=> x = -18

2/ ko hỉu đề

\(\left(27.700-45.20\right)\div\left(45-40+35-30+25-20+15-10+5\right)\)

\(=\)\(\left(27.100-45.20\right)\div25\)

\(=\)\(\left(27.35.20-45.20\right)\div25\)

\(=\)\(\left[\left(27.35-45\right).20\right]\div25\)

\(=\)\(18000\div25\)

\(=\)\(750\)

\(I=\frac{\frac{25}{17}-\frac{25}{27}-\frac{25}{37}-\frac{25}{47}}{\frac{45}{17}-\frac{45}{27}-\frac{45}{37}-\frac{45}{47}}\)

\(I=\frac{25.\left(\frac{1}{17}-\frac{1}{27}-\frac{1}{37}-\frac{1}{47}\right)}{45.\left(\frac{1}{17}-\frac{1}{27}-\frac{1}{37}-\frac{1}{47}\right)}\)

\(I=\frac{25}{45}=\frac{5}{9}\)

`@` `\text {Ans}`

`\downarrow`

`c)`

`( 34 - 2x ) . ( 2x - 6 ) = 0`

`=>`\(\left[{}\begin{matrix}34-2x=0\\2x-6=0\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}2x=34\\2x=6\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=34\div2\\x=6\div2\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=17\\x=3\end{matrix}\right.\)

Vậy, `x \in {17; 3}`

`d)`

`( 2019 - x ) . ( 3x - 12 ) =0` `?`

`=>`\(\left[{}\begin{matrix}2019-x=0\\3x-12=0\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019-0\\3x=12\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019\\x=12\div3\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019\\x=4\end{matrix}\right.\)

Vậy, `x \in {2019; 4}`

`e) `

`57 . ( 9x - 27 ) = 0`

`=>`\(9x-27=0\div57\)

`=> 9x - 27 = 0`

`=> 9x = 27`

`=> x = 27 \div 9`

`=> x = 3`

Vậy, `x = 3`

`f)`

`25 + ( 15 - x ) = 30`

`=> 15 - x = 30 - 25`

`=> 15 - x = 5`

`=> x = 15 -5 `

`=> x = 10`

Vậy, `x = 10`

`g) `

`43 - ( 24 - x ) = 20`

`=> 24 - x = 43 - 20`

`=> 24 - x = 23`

`=> x = 24 - 23`

`=> x = 1`

Vậy, `x = 1`

`h) `

`2 . ( x - 5 ) - 17 = 25`

`=> 2 ( x - 5) = 25+17`

`=> 2 ( x - 5) = 42`

`=> x - 5 = 42 \div 2`

`=> x - 5 = 21`

`=> x = 21 + 5`

`=> x = 26`

Vậy, `x = 26`

`i)`

`3 . ( x + 7 ) - 15 = 27`

`=> 3(x + 7) = 27 + 15`

`=> 3(x + 7) = 42`

`=> x +7 = 42 \div 3`

`=> x + 7 = 14`

`=> x = 14 - 7`

`=> x = 7`

Vậy, `x = 7`

`j)`

`15 + 4 . ( x - 2 ) = 95`

`=> 4(x - 2) = 95 - 15`

`=> 4(x - 2) = 80`

`=> x - 2 = 80 \div 4`

`=> x - 2 = 20`

`=> x = 20 + 2`

`=> x = 22`

Vậy, `x = 22`

`k)`

`20 - ( x + 14 ) = 5`

`=> x + 14 = 20 - 5`

`=> x + 14 = 15`

`=> x = 15 - 14`

`=> x = 1`

Vậy, `x = 1`

`l) `

`14 + 3 . ( 5 - x ) = 27`

`=> 3(5 - x) = 27 - 14`

`=> 3(5 - x) = 13`

`=> 5 - x = 13 \div 3`

`=> 5 - x = 13/3`

`=> x = 5- 13/3`

`=> x = 2/3`

Vậy, `x = 2/3.`

`@` `\text {Kaizuu lv uuu}`

nhanh mik tick cho nha

Tập hợp các số nguyên x thỏa mãn 45 - | -27 - ( -25 ) - x | = 20 là { -25,-23 }

Tập hợp các số nguyên x thỏa mãn 45 - | -27 - ( -25 ) - x | = 20

=>45-|-27+25-x|=20

|-27+25-x|=45-20

=>|-27+25-x|=25  hoac |-27+25-x|=-25

=>|2-x|=25      hoac    |2-x|=-25

x=-23               hoac   x=27

B10:

a)23.27=621

b)-23.27=-621

c)23.(-23)=529

d)(-23).(-27)=621

Bằng 2.

Mình giải rồi.Đúng 100%

giải giùm ra ik "bố thích chết"

=>45-|-2-x|=20

=>|-2-x|=45-20

=>|-2-x|=25

TH1:-2-x=25

=>x=-2-25

=>x=-27

TH2:-2-x=-25

=>x=-2-(-25)

=>x=23

Vậy x thuộc {-27;23}

Tk mik nha

45 - | 27 - ( - 25 ) - x | = 20

       | 27 + 25 - x | = 45 - 20

       | 50 - x | = 25

=> \(\orbr{\begin{cases}50-x=25\\50-x=-25\end{cases}}\)       => \(\orbr{\begin{cases}x=50-25=25\\x=50-\left(-25\right)=75\end{cases}}\)

Vậy x \(\in\){ 25 ; 75 }

32/72

20/45

32/72