Bài 1: Tìm x a, 46 - x = 95 b, ( - 3) . x - 1= 8 c, 3 mũ x + 15 = 24 Bài 2: Tìm x a, x + 7= -5 b, (x + 73) - 26 = 14 c, 2 mũ x : 2 mũ 5 = 1 Bài 3: Tìm x a, x- 25= -34 b, 35 - 5.( x -1)= 50 c, 4 . 2 mũ x - 3= 125 Bài 4: Tìm số nguyên x, biết a, x+ 15= -25 b, 4 . ( x-3)=28 c, 4 mũ x-1 + 3=67

Bài `1` : 
`a) 46 - x = 95`

`x = 46 - 95`

`x = -49` 

Vậy `x = -49`

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`b) (-3) . x -1 = 8`

`(-3) . x = 8 + 1`

`(-3) . x = 9`

`x = 9 : (-3)`

`x = -3`

Vậy `x = -3`

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`c) 3^x + 15 = 24`

`3^x = 24 - 15`

`3^x = 9`

`=> 3^x = 3^2`

`=> x = 2`

Vậy `x = 2`

Bài `2` ; 
`a) x + 7 = -5`

`x = -5 - 7`

`x = -12`

Vậy `x = -12`

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`b) (x + 73) - 26 = 14`

`x + 73 = 14 + 26`

`x + 73 = 40`

`x = 40 - 73`

`x = -33`

Vậy `x = -33`

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`c) 2^x : 2^5 = 1`

`2^x : 2^5 = 2^0`

`2^x = 2^0 . 2^5`

`2^x = 2^5`

`=> x = 5`

Vậy `x = 5`

Bài `3` : 
`a) x - 25 = -34`

`x = -34 + 25`

`x = -9`

Vậy `x = -9`

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`b) 35 - 5 . (x - 1) = 50`

`5 . (x - 1) = 35 - 50`

`5 . (x - 1) -15`

`x - 1 = -15 : 5`

`x - 1 = -3`

`x = -3 + 1`

`x = -2`

Vậy `x = -2`

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`c) 4 .2^x - 3 = 125`

`4. 2^x = 125 + 3`

`4 . 2^x = 128`

`2^x = 32`

`=> 2^x = 2^5`

`=> x = 5`

Vậy `x = 5`

Bài `4` : 
`a) x + 15 = -25`

`x = -25 - 15`

`x = -40`

Vậy `x = -40`

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`b) 4 . (x - 3) = 28`

`x - 3 = 28 : 4`

`x - 3 = 7`

`x = 7 + 3`

`x = 10`

Vậy `x = 10`

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`c) 4^(x - 1) + 3 = 67`

`4^(x - 1) = 67 - 3`

`4^(x - 1) = 64`

`=> 4^(x - 1) = 4^3`

`=> x - 1 = 3`

`x = 3 + 1`

`x = 4`

Vậy `x = 4`

`@Christian`