Question

phương trình 4/3x-2 trừ 7/x+1=0 có nghiệm là; 

giúp mình với

Answer 1

4/(3x - 2) - 7/(x + 1) = 0

<=> 4(x + 1) - 7(3x - 2) = 0

<=> 4x + 4 - 21x + 14 = 0

<=> -17x + 18 = 0

<=> -17x = 0 - 18

<=> -17x = -18

<=> x = 18/17

Answer 2

Ta có : \(\frac{4}{3x-2}-\frac{7}{x+1}=0\)

\(\Leftrightarrow\frac{4}{3x-2}-\frac{7}{x-1}=0,x\ne\frac{2}{3},x\ne-1\)

\(\Leftrightarrow\frac{4.\left(x+1\right)-7.\left(3x-2\right)}{\left(3x-2\right).\left(x+1\right)}=0\)

\(\Leftrightarrow\frac{4x+4-21x+14}{\left(3x-2\right).\left(x+1\right)}=0\)

\(\Leftrightarrow\frac{-17x+18}{\left(3x-2\right).\left(x+1\right)=0}\)

\(\Leftrightarrow-17.x+18=0\)

\(\Leftrightarrow-17.x=-18\)

\(\Leftrightarrow x=\frac{18}{17},x\ne\frac{2}{3},x\ne-1\)