[tex]\it 0,(3)x^2 = \dfrac{27}{256} \Leftrightarrow \dfrac{1}{3}x^2 = \dfrac{27}{256} \Leftrightarrow x^2 = \dfrac{27}{256} \cdot\dfrac{3}{1}\Leftrightarrow x^2 = \dfrac{81}{256} \Leftrightarrow
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\Leftrightarrow \sqrt{x^2} = \sqrt{\dfrac{81}{256}} \Leftrightarrow |x| = \dfrac{9}{16}\Leftrightarrow x=\pm\dfrac{9}{16} [/tex]
