Đáp án + Giải thích các bước giải:
1/ `|x - 7| = 0 => x - 7 = 0=> x=7`
2/`|x + 3| = 6 => `\(\left[ \begin{array}{l}x + 3=6\\x+3=-6\end{array} \right.\) $\\$ `=>` \(\left[ \begin{array}{l}x=3\\x=-9\end{array} \right.\)
3/ `|2x + 4| + 15= 35` $\\$ `=> |2x + 4| = 35 - 15` $\\$ `=> |2x + 4| = 20` $\\$ `=>` \(\left[ \begin{array}{l}2x+4=20\\2x + 4 = -20\end{array} \right.\) $\\$ `=>` \(\left[ \begin{array}{l}2x=16\\2x=-24\end{array} \right.\) $\\$ `=>` \(\left[ \begin{array}{l}x=8\\x=-12\end{array} \right.\)
