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

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

1. x=69/10

2. x =59/8

4. x=301/300

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