Đáp án: x=14
Giải thích các bước giải:
$\begin{array}{l}
\frac{{x - 1}}{{13}} - \frac{{2x - 13}}{{15}} = \frac{{3x - 15}}{{27}} - \frac{{4x - 27}}{{29}}\\
\Rightarrow \frac{{x - 1}}{{13}} - 1 - \left( {\frac{{2x - 13}}{{15}} - 1} \right) = \frac{{3x - 15}}{{27}} - 1 - \left( {\frac{{4x - 27}}{{29}} - 1} \right)\\
\Rightarrow \frac{{x - 14}}{{13}} - \frac{{2x - 28}}{{15}} = \frac{{3x - 42}}{{27}} - \frac{{4x - 56}}{{29}}\\
\Rightarrow \left( {x - 14} \right).\left( {\frac{1}{{13}} - \frac{2}{{15}} - \frac{1}{{27}} + \frac{1}{{29}}} \right) = 0\\
\Rightarrow x = 14
\end{array}$
