$|x+3|=15$
⇔\(\left[ \begin{array}{l}x+3=15\\x+3=-15\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=12\\x=-18\end{array} \right.\)
$|x-7|+13=25$
⇔$|x-7|=12$
⇔\(\left[ \begin{array}{l}x-7=12\\x-7=-12\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=19\\x=-5\end{array} \right.\)
$|x-3|-16=-4$
⇔$|x-3|=12$
⇔\(\left[ \begin{array}{l}x-3=12\\x-3=-12\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=15\\x=-9\end{array} \right.\)
