a: \(\frac{x}{3}=\frac{2}{y}\)
=>\(xy=2\cdot3=6\)
=>(x;y)∈{(1;6);(6;1);(-1;-6);(-6;-1);(2;3);(3;2);(-2;-3);(-3;-2)}
b: \(\frac{-3}{x}=\frac{y}{2}\)
=>\(xy=-3\cdot2=-6\)
=>(x;y)∈{(1;-6);(-6;1);(-1;6);(6;-1);(2;-3);(-3;2);(-2;3);(3;-2)}
c: \(\frac{x}{y}=\frac34\)
=>\(\frac{x}{y}=\frac{3k}{4k}\)
=>x=3k; y=4k(k∈Z; k<>0)
d: \(\frac{x}{6}=\frac{y}{8}\)
=>\(\frac{x}{3}=\frac{y}{4}=k\)
=>x=3k; y=4k(k∈Z)
