tinh chat cua day ti so bang nhau

B

braga

Theo đề bài ta có:

[TEX]\frac{x}{3}=\frac{y}{2} \ va \ x-y=20[/TEX]

[TEX]\frac{x}{3}=\frac{y}{2}=\frac{x-y}{3-2}=\frac{20}{1}=20[/TEX]

[TEX]\Rightarrow x=20.3=60 \ ; \ y=20.2=40[/TEX]
 
H

harrypham

C1: [TEX]\frac{x}{3}= \frac{y}{2} = \frac{x-y}{3-2}=20[/TEX]
[TEX]\Rightarrow x=20.3= \fbox{60}, \ \ y=20.2= \fbox{40}[/TEX].

C2: [TEX]\frac{x}{3}= \frac{y}{2}=k \Rightarrow x=3k, \ y=2k[/TEX].
[TEX]\Rightarrow x-y=3k-2k = k = 20 \Rightarrow x=60, \ y=40[/TEX].

C3: [TEX]\frac{x}{3}= \frac{y}{2} \Rightarrow 2x=3y \Rightarrow 2x-2y=3y-2y[/TEX]
[TEX]\Rightarrow 2(x-y)=y \Rightarrow y=40 \Rightarrow x=60[/TEX].
 
You must log in or register to reply here.
Top Bottom