`@` `\text {Ans}`
`\downarrow`
`1,`
`a)`
`x + 12 = 25`
`\Rightarrow x = 25 - 12`
`\Rightarrow x = 13`
Vậy, `x = 13`
`b)`
`134 - x = 125 \div 5`
`\Rightarrow 134 - x = 25`
`\Rightarrow x = 134 - 25`
`\Rightarrow x=109`
Vậy, `x = 109`
`c)`
`2 \times x - 53 = 22`
`\Rightarrow 2x = 22 + 53`
`\Rightarrow 2x = 75`
`\Rightarrow x = 75 \div 2`
`\Rightarrow x =37,5`
Vậy, `x = 37,5`
`d)`
`7 + 3 \times x = 16`
`\Rightarrow 3x = 16 - 7`
`\Rightarrow 3x =9`
`\Rightarrow x = 9 \div 3`
`\Rightarrow x = 2`
Vậy, `x = 2.`
`2,`
`a)`
`(x + 3) - 15 = 2`
`\Rightarrow x + 3 = 2 + 15`
`\Rightarrow x +3 = 17`
`\Rightarrow x = 17 - 3`
`\Rightarrow x = 14`
Vậy, `x = 14`
`b)`
`33 + (x - 1) = 56`
`\Rightarrow x - 1 = 56 - 33`
`\Rightarrow x - 1 = 23`
`\Rightarrow x = 23 + 1`
`\Rightarrow x = 24`
Vậy, `x = 24`
`c)`
`5 \times (4 + 6 \times x) = 290`
`\Rightarrow 4 + 6x = 290 \div 5`
`\Rightarrow 4 + 6x = 58`
`\Rightarrow 6x = 58 - 4`
`\Rightarrow 6x = 54`
`\Rightarrow x = 54 \div 6`
`\Rightarrow x = 9`
Vậy, `x = 9`
`d)`
`x. 3,7 + x. 6,3 = 120`
`\Rightarrow x . (3,7 + 6,3) = 120`
`\Rightarrow x . 10 = 120`
`\Rightarrow x = 120 \div 10`
`\Rightarrow x = 12`
Vậy,` x = 12.`
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