A $\frac{2}{3}$ = $\frac{x}{6}$
=> 2.6=3x
12=3x
x=4
B $\frac{4}{x}$ =2
=> 4.1=2x
4=2x
x=2
C $\frac{2}{x}$ = $\frac{y}{6}$ = $\frac{6}{9}$
Ta có $\frac{2}{x}$ = $\frac{y}{6}$ = $\frac{6}{9}$ = $\frac{2}{3}$
=> $\frac{2}{x}$ = $\frac{2}{3}$
x= = $\frac{2.3}{3}$ =2
=> $\frac{y}{6}$ = $\frac{2}{3}$
y=$\frac{2.6}{3}$=4