x+3/5=15/2 -4-x/-2=-5/16 -3/5=-1/5-15/21 4x/-7=-6/25-5/15
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#andy
\[\begin{array}{l}
a)x + \dfrac{3}{5} = \dfrac{{15}}{2}\\
\Leftrightarrow x = \dfrac{{15}}{2} - \dfrac{3}{5}\\
\Leftrightarrow x = \dfrac{{69}}{{10}}\\
b)\dfrac{{ - 4 - x}}{{ - 2}} = - \dfrac{5}{{16}}\\
\Leftrightarrow \dfrac{{ - \left( {4 + x} \right)}}{{ - 2}} = - \dfrac{5}{{16}}\\
\Leftrightarrow \dfrac{{4 + x}}{2} = - \dfrac{5}{{16}}\\
\Leftrightarrow 4 + x = - \dfrac{5}{8}\\
\Leftrightarrow x = - \dfrac{{37}}{8}\\
c) - \dfrac{3}{5} = - \dfrac{1}{5} - \dfrac{{15}}{{21}}\\
\Rightarrow Sai\,\,đề\\
d)\dfrac{{4x}}{{ - 7}} = - \dfrac{6}{{25}} - \dfrac{5}{{15}}\\
\Leftrightarrow - \dfrac{{4x}}{7} = - \dfrac{{43}}{{75}}\\
\Leftrightarrow - 4x = - \dfrac{{301}}{{75}}\\
\Leftrightarrow x = \dfrac{{301}}{{300}}
\end{array}\]
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