Tính: \(\dfrac{{ - 1}}{6} - \dfrac{{ - 4}}{9}\)

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Cả A, B, C đều đúng

$\dfrac{{ - 2}}{3};\dfrac{3}{2}$                 

$\dfrac{{ - 12}}{{13}};\dfrac{{13}}{{ - 12}}$  

\(\dfrac{1}{2}; - \dfrac{1}{2}\)

\(\dfrac{3}{4};\dfrac{{ - 4}}{3}\)

\(\dfrac{{27}}{2}\) 

\( - \left( { - \dfrac{2}{{27}}} \right)\)  

\(\dfrac{2}{{27}}\)

\( - \dfrac{2}{{27}}\)

$\dfrac{{ - 53}}{{35}}$ 

\(\dfrac{{51}}{{35}}\)  

\(\dfrac{{ - 3}}{{35}}\)                  

\(\dfrac{3}{{35}}\)

$\dfrac{3}{2} + \dfrac{2}{3} > 1$ 

$\dfrac{3}{2} + \dfrac{2}{3} = \dfrac{{13}}{6}$     

$\dfrac{3}{4} + \left( {\dfrac{{ - 4}}{{17}}} \right) = \dfrac{{35}}{{68}}$

$\dfrac{4}{{12}} + \dfrac{{21}}{{36}} = 1$

\(x = \dfrac{{21}}{{20}}\)

\(x = \dfrac{{29}}{{20}}\)      

\(x = \dfrac{{ - 3}}{{10}}\)     

\(x = \dfrac{{ - 9}}{{10}}\)