18+3(x-3)=63 [(2x-11):3+1]x5=20 25-3x(6-X) =22

Đáp án `+` Giải thích các bước giải:

`18 + 3( x - 3 ) = 63`

`=> 3 ( x - 3 ) = 63 - 18`

`=> 3 ( x - 3) = 45`

`=> x - 3 = 45 : 3`

`=> x - 3 = 15`

`=> x = 15 + 3`

`=> x = 18`

Vậy `x = 18`

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`[(2x - 11) : 3 + 1] xx 5 = 20`

`=> [(2x - 11) : 3 + 1] = 20 : 5`

`=> (2x - 11) : 3 + 1 = 4`

`=> ( 2x - 11 ) : 3 = 4 - 1`

`=> ( 2x -11 ) : 3 = 3`

`=> 2x - 11  = 3 xx 3`

`=> 2x - 11 = 9`

`=> 2x = 11 +9 `

`=> 2x = 20`

`=> x = 20 : 2`

`=> x = 10`

Vậy `x = 10`

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`25 - 3 xx (6 - x ) = 22`

`=> 3 xx ( 6 - x ) = 25 - 22`

`=> 3 xx ( 6 - x ) = 3`

`=> 6 - x = 3 : 3`

`=> 6 - x = 1`

`=> x = 6 - 1`

`=> x = 5`

Vậy `x = 5`