b)\(\frac{x-2}{x+1}=\frac{3}{4}\)
\(\Leftrightarrow4x\left(x-2\right)-3\left(x+1\right)=0\)
\(\Leftrightarrow4x-8-3x-3=0\)
\(\Leftrightarrow4x-3x=8+3\)
\(\Leftrightarrow x=11\)
CÒN CÂU A MK CHƯA HIỂU ĐỀ LẮM Ạ!
b) \(\frac{x-2}{x+1}=\frac{3}{4}\)
\(\Rightarrow\left(x-2\right).4=\left(x+1\right).3\)
\(\Rightarrow4x-8=3x+3\)
\(\Rightarrow4x-3x=3+8\)
\(\Rightarrow1x=11\)
\(\Rightarrow x=11:1\)
\(\Rightarrow x=11\)
Vậy \(x=11.\)
Chúc bạn học tốt!