Cho \(\dfrac{{15}}{x} = \dfrac{5}{7}\) thì giá trị $x$ là:

$x = 4$                          

$x\; = -4$                   

$x = 4$ hoặc $x = -4$            

$x = 0$

\(\) \(\dfrac{{245}}{{100}}\)             

\(\dfrac{{245}}{{1000}}\)                  

\(\dfrac{{49}}{{500}}\)               

\(\dfrac{{49}}{{200}}\)

\(\dfrac{{12}}{6}\, = \,\dfrac{9}{8}\,\)

\(\dfrac{8}{6}\, = \,\dfrac{{12}}{9}\,\)           

\(\dfrac{6}{{12}}\, = \,\dfrac{8}{9}\,\)           

\(\dfrac{6}{8}\, = \,\dfrac{{12}}{9}\,\)

\(49\)                            

\( - 49\)

\(7\)  và \( - 7\)

\(7\)    

\(448,6\)          

\(448\)

\(450\)

\(448,58\)        

\(\,{\left( { - \,3} \right)^6}\)                  

\(\,{\left( { - \,3} \right)^2}\)   

\(\,{\left( { - \,3} \right)^8}\)              

\(\,{\left( { - \,3} \right)^5}\)

$ - \dfrac{5}{2}$                    

$ - 1$

$ - \dfrac{5}{4}$        

$ - \dfrac{2}{5}$