\(a,\dfrac{x}{3}=\dfrac{6}{-9}\\ \Rightarrow x=-\dfrac{2}{3}.3\\ \Rightarrow x=-2\\ b,\dfrac{4}{y}=\dfrac{-2}{-5}\\ \Rightarrow y=4:\dfrac{2}{5}\\ \Rightarrow y=10\\ c,\dfrac{-2}{3}=\dfrac{x-1}{6}\\ \Rightarrow3x-3=-12\\ \Rightarrow3x=-9\\ \Rightarrow x=-3\\ d,\dfrac{3}{x}=\dfrac{6}{-24}\\ \Rightarrow x=3:-\dfrac{1}{4}\\ \Rightarrow x=-12\)
a: x=18/(-9)=-2
b: =>y=5x4:2=10
c: =>x-1=-4
=>x=-3
d: =>3/x=-1/4
hay x=-12
a)\(x=-2\)
b) \(y=10\)
c) \(x=-5\)
d) \(x=-12\)
a) \(\dfrac{x}{3}\)= \(\dfrac{9}{-9}\)
-> x . (-9) = 9 . 3
x . (-9) = 27
x = 27 : (-9)
x = -3
Câu b , d làm tương tự câu a bằng cách nhân chéo rồi tìm x
c) \(\dfrac{-2}{3}\)= \(\dfrac{x-1}{6}\)
-> 3 . ( x-1) = -2 . 6
3 . ( x-1) = -12
( x-1) = -12 : 3
x - 1 = -4
x = -4 + 1
x = -3
