`5x - 12 = 43`
`⇔5x = 43 + 12`
`⇔5x =55`
`⇔x = 55: 5`
`⇔x = 11`
` - - - - - -- --`
`|x - 5| - 21 = -8`
`⇔|x - 5| = -8 + 21`
`⇔|x- 5| = 13`
`⇔` \(\left[ \begin{array}{l}x- 5 = 13\\x - 5 = -13\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x=18\\x=-8\end{array} \right.\)
`- - ---- - - -`
`( x - 6). (-3 + 15) = 0`
`⇔`\(\left[ \begin{array}{l}x - 6 = 0\\-3x + 15 = 0\end{array} \right.\)
`⇔`\(\left[ \begin{array}{l}x=6\\-3x = -15\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x=6\\x=5\end{array} \right.\)
`- - - - -- - -`
`18 - 5x = -12`
`⇔5x = 18 - (-12)`
`⇔5x = 30`
`⇔x = 30 : 5`
`⇔x = 6`
`- - -- - - - -`
`|x -2| = 3`
`⇔`\(\left[ \begin{array}{l}x - 2 = 3\\x - 2 = -3\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x=5\\x=-1\end{array} \right.\)
