`a)-(x-19)-(x-17)+3x-25=-9`
`→-x+19-x+17+3x-25=-9`
`→-x-x+3x=-9-19-17+25`
`→x=-20`
Vậy `x=-20`
`b)(x-3)+(5-2x)=-119+(-7)`
`→x-3+5-2x=-126`
`→x-2x=-126+3-5`
`→-x=-128`
`→x=128`
Vậy `x=128`
`c)|2x-1|=(59-19)-(-8-12)`
`→|2x-1|=40-(-20)`
`→|2x-1|=60`
`→` \(\left[ \begin{array}{l}2x-1=60\\2x-1=-60\end{array} \right.\)
`→` \(\left[ \begin{array}{l}2x=61\\2x=-59\end{array} \right.\)
`→` \(\left[ \begin{array}{l}x=\dfrac{61}{2}\\x=\dfrac{-59}{2}\end{array} \right.\)
Vậy `x∈{61/2;-59/2}`
