a, |x-2|=3
⇔\(\left[ \begin{array}{l}x-2=3\\x-2=-3\end{array} \right.\)⇔\(\left[ \begin{array}{l}x=5\\x=-1\end{array} \right.\)
Vậy x=5 hoặc x=-1
b, |x-3|-7=13
⇔|x-3|=20
⇔\(\left[ \begin{array}{l}x-3=20\\x-3=-20\end{array} \right.\)⇔\(\left[ \begin{array}{l}x=23\\x=-17\end{array} \right.\)
Vậy x=23 hoặc x=-17
c, -12(x-5)+7(3-x)=5
⇔-12x+60+21-7x=5
⇔-12x-7x=5-60-21
⇔-19x=-76
⇔x=4
Vậy x=4.
