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Absolute Value (in equations)

Find the value(s) of $x$:

  1. $|x+1|=2  \rightarrow x+1=2 \text{ and } x+1=-2\rightarrow \mathbf{x=1,-3}$
  2. $|x-5|=-5  \rightarrow \mathbf{\text{no solution}}$
  3. $|x-5|=5  \rightarrow x-5=5 \text{ and } x-5=-5\rightarrow\mathbf{x=10,0}$
  4. $|5x|=10  \rightarrow 5x=10 \text{ and } 5x=-10\rightarrow\mathbf{x=2,-2}$
  5. $|2x|=3  \rightarrow 2x=3 \text{ and }2x=-3\rightarrow\mathbf{x=\dfrac{3}{2},\dfrac{-3}{2}}$
  6. $|\dfrac{x}{2}|=6 \rightarrow \dfrac{x}{2}=6 \text{ and } \dfrac{x}{2}=-6\rightarrow\mathbf{x=12,-12}$
  7. $|\dfrac{x}{3}|=10\rightarrow \dfrac{x}{3}=10 \text{ and } \dfrac{x}{3}=-10\rightarrow\mathbf{x=30,-30}$
  8. $|\dfrac{1}{x}|=2 \rightarrow \dfrac{1}{x}=2 \text{ and } \dfrac{1}{x}=-2\rightarrow\mathbf{x=\dfrac{1}{2},\dfrac{-1}{2}}$
  9. $|3x+4|=12\rightarrow 3x+4=12 \text{ and }3x+4=-12\rightarrow\mathbf{x=\dfrac{8}{3},\dfrac{-16}{3}}$
  10. $|12x-7|=20\rightarrow 12x-7=20 \text{ and }12x-7=-20\rightarrow\mathbf{x=\dfrac{9}{4},\dfrac{-13}{12}}$
  11. $|\dfrac{2x+1}{2}|=10  \rightarrow \dfrac{2x+1}{2}=10 \text{ and } \dfrac{2x+1}{2}=-10\rightarrow\mathbf{x=\dfrac{19}{2},\dfrac{-21}{2}}$
  12. $|\dfrac{9x-10}{5}|=3  \rightarrow \dfrac{9x-10}{5}=3 \text{ and } \dfrac{9x-10}{5}=-3\rightarrow\mathbf{x=\dfrac{25}{9},\dfrac{-5}{9}}$