b) \(\dfrac{-6}{x}=\dfrac{30}{35}=>-6\) x 35 = \(x\) x 30
=> -210 = \(x\) x 30
=> \(x\)= -210 : 30
=> \(x\)= -7
c) ( 4,5 - \(x\)) : \(\dfrac{11}{7}\)= \(\dfrac{14}{11}\)
=> 4,5 - \(x\)= \(\dfrac{14}{11}\)x \(\dfrac{11}{7}\)
=>4,5 - \(x\)= 2
=> \(x\)= 4,5 - 2
=> \(x\)= 2,5
b: -6/x=30/35=6/7
nên x=-7
c: =>9/2-x=14/11x11/7=2
=>x=9/2-2=5/2