\(\frac{5x-2y}{x+3y}=chong.copy.linhtinh\Leftrightarrow20\left(\frac{x}{y}\right)-8=7\left(\frac{x}{y}\right)+21\Rightarrow13\left(\frac{x}{y}\right)=29\)

 \(\Rightarrow copy.linhtinh=bieuthuc\)không hiểu nhận được qua tin nhắn (hiểu rồi thì càng tốt)

\(\frac{x}{y}=\frac{29}{13}\)

\(\frac{5-2x}{x+3y}=\frac{7}{4}\)

\(\frac{5x-2y}{x+3y}=\frac{7}{4}\)

\(20x-8y=7x+21y\)

\(13x=29y\)

\(\frac{x}{y}=\frac{29}{13}\)

\(\frac{5x-2y}{x+3y}=\frac{7}{4}\)

=> (5x - 2y).4 = 7.(x + 3y)

=> 20x - 8y = 7x + 21y

=>> 20x - 7x = 21y + 8y

=> 13x = 29y

\(\Rightarrow\frac{x}{y}=\frac{29}{13}\)

\(\frac{5x-2y}{x+3y}=\frac{7}{4}\)

\(\Rightarrow4\left(5x-2y\right)=7\left(x+3y\right)\)

\(\Rightarrow20x-8y=7x+21y\)

\(\Rightarrow20x-7x=8y+21y\)

\(\Rightarrow13x=29y\)

\(\Rightarrow\frac{x}{y}=\frac{29}{13}\)

Vậy \(\frac{x}{y}=\frac{29}{13}\)

\(\frac{5x-2y}{x+3y}=\frac{7}{4}\)

\(\Rightarrow7\left(x+3y\right)=4\left(5x-2y\right)\)

\(\Rightarrow7x+21y=20x-8y\)

\(\Rightarrow7x-20x=-8y-21y\)

\(\Rightarrow-13x=-29y\)

\(\Rightarrow13x=29y\)

\(\Rightarrow\frac{x}{y}=\frac{29}{13}\)

Vậy : \(\frac{x}{y}=\frac{29}{13}\)

Câu 3.\(\frac{5x-2y}{x+3y}=\frac{7}{4}\)

=> \(4\left(5x-2y\right)=7\left(x+3y\right)\)

=> \(20x-8y=7x+21y\)

=> \(20x-7x=21y-8y\)

=> 13x = 13y

=> x = y

=> \(\frac{x}{y}=1\)

Theo đế bài ta có:

\(20x-8y=7x+21y\)

\(\Leftrightarrow20x-7x=21y+8y\)

\(13x=21y\)

\(\Rightarrow\frac{x}{y}=\frac{21}{13}\)

\(\frac{5x-2y}{x+3y}=\frac{7}{4}\)

\(\Rightarrow4\cdot\left(5x-2y\right)=7\cdot\left(x+3y\right)\)

20x - 8y = 7x + 21y

20x - 7x = 21y + 8y

13x = 29y

\(\Rightarrow\frac{x}{y}=\frac{29}{13}\)

\(\frac{5x-2y}{x+3y}=\frac{7}{4}\) => 4. (5x - 2y) = 7.(x+ 3y) => 20x - 8y = 7x + 21y

=> 20x - 7x = 8y + 21y => 13x = 29y => \(\frac{x}{y}=\frac{29}{13}\)

= 29/13

Ta có:\(\orbr{\begin{cases}2x-3y=3\\x+2y=2\end{cases}}\)\(\Leftrightarrow\)\(\orbr{\begin{cases}4x-6y=6\\3x+6y=6\end{cases}}\)\(\Leftrightarrow\)\(\orbr{\begin{cases}7x=12\\3x+6y=6\end{cases}}\)\(\Leftrightarrow\)\(\orbr{\begin{cases}x=\frac{12}{7}\\3x+6y=6\end{cases}}\)

\(\Leftrightarrow\)\(\orbr{\begin{cases}x=\frac{12}{7}\\y=\frac{1}{7}\end{cases}}\)

Vậy tỉ lệ thức \(\frac{y}{x}=\frac{1}{12}\)

Ta có:

\(\left(2x-3y\right).3=\left(x+2y\right).2\)

\(2x.3-3y.3=x.2+2y.2\)

\(6x-9y=2x+4y\)

\(6x-2x=9y+4y\)

\(4x=13y\)

Chia hai vế cho 4y, ta có:

\(\frac{4x}{4y}=\frac{13y}{4y}\)

\(=\frac{x}{y}=\frac{13}{4}\)

\(\Rightarrow\) Tỉ số giữa x và y là \(\frac{13}{4}\)

Ta có:

\(\frac{2x-3y}{x+2y}=\frac{2}{3}\)

<=> 3(2x-3y)= 2(x+2y)

<=> 6x - 9y = 2x + 4y

<=> 6x - 2x = 9y+4y

<=> 4x = 13y

=> \(\frac{x}{y}=\frac{13}{4}\)

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