Đáp án `+` Giải thích các bước giải:

`1,` `180 - 80 : (20 - 2x) = 172`

`80 : (20 - 2x) = 8`

`20 - 2x = 10`

`2x = 10`

`x = 5`

Vậy `x = 5`

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`2,` `145 : 5 + 15 : (2x - 1) = 2^5`

`29 + 15 : (2x - 1) = 32`

`15 : (2x - 1) = 3`

`2x - 1 = 5`

`2x = 6`

`x = 3`

Vậy `x = 3`

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`3,` `2x + 3x - 4 = 21`

`5x = 25`

`x = 5`

Vậy `x = 5`

`\text{}`

`4,` `5x + 3x + 7 = 23`

`8x = 16`

`x = 2`

Vậy `x = 2`

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`5,` `2^(x+2) = 32`

`2^(x+2) = 2^5`

`=> x + 2 = 5`

`x = 3`

Vậy `x = 3`

`\text{}`

`6,` `5 xx 3^(4-x) - 2 = 43`

`5 xx 3^(4 - x) = 45`

`3^(4-x) = 9`

`3^(4-x) = 3^2`

`=> 4 - x = 2`

`x = 2`

Vậy `x = 2`

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`7,` `4(3x - 1)^3 = 600`

`(3x - 1)^3 = 150` (vô lí)

Vậy không có giá trị `x` thỏa mãn

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`8,` `5(2x - 1)^2 - 1 = 44`

`5(2x - 1)^2 = 45`

`(2x - 1)^2 = 9`

`(2x - 1)^2 = 3^2 = (-3)^2`

Ta xét `2` TH sau:

TH1: `2x - 1 = 3`

`2x = 4`

`x = 2`

TH2: `2x - 1 = -3`

`2x = -2`

`x = -1`

Vậy `x \in {2 ; -1}`

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