Bài giải :

$2\,\,.\,\,{{3}^{x}}=10\,\,.\,\,{{3}^{12}}+8\,\,.\,\,{{27}^{4}}$

$\Leftrightarrow 2\,\,.\,\,{{3}^{x}}=10\,\,.\,\,{{3}^{12}}+8\,\,.\,\,{{\left( {{3}^{3}} \right)}^{4}}$

$\Leftrightarrow 2\,\,.\,\,{{3}^{x}}=10\,\,.\,\,{{3}^{12}}+8\,\,.\,\,{{3}^{12}}$

$\Leftrightarrow 2\,\,.\,\,{{3}^{x}}={{3}^{12}}\left( 10+8 \right) $

$\Leftrightarrow 2\,\,.\,\,{{3}^{x}}={{3}^{12}}.18$

$\Leftrightarrow 2\,\,.\,\,{{3}^{x}}={{3}^{12}}\,.\,{{3}^{2}}\,.\,2$

$\Leftrightarrow 2\,\,.\,\,{{3}^{x}}= 2\,\,.\,\,{{3}^{14}}$

$\Leftrightarrow {{3}^{x}}={{3}^{14}}$

$\Leftrightarrow x=14$.