NV

\(\frac{X+1}{9}+\frac{X+2}{8}=\frac{X+3}{7}+\frac{X+4}{6}\)

TP
4 tháng 3 2019 lúc 19:52

\(\frac{x+1}{9}+\frac{x+2}{8}=\frac{x+3}{7}+\frac{x+4}{6}\)

\(\Leftrightarrow\frac{x+1}{9}+1+\frac{x+2}{8}+1=\frac{x+3}{7}+1+\frac{x+4}{6}+1\)

\(\Leftrightarrow\frac{x+10}{9}+\frac{x+10}{8}=\frac{x+10}{7}+\frac{x+10}{6}\)

\(\Leftrightarrow\frac{x+10}{9}+\frac{x+10}{8}-\frac{x+10}{7}-\frac{x+10}{6}=0\)

\(\Leftrightarrow\left(x+10\right)\left(\frac{1}{9}+\frac{1}{8}-\frac{1}{7}-\frac{1}{6}\right)=0\)

Vì \(\frac{1}{9}+\frac{1}{8}-\frac{1}{7}-\frac{1}{6}\ne0\)

\(\Leftrightarrow x+10=0\)

\(\Leftrightarrow x=-10\)

Vậy....

Bình luận (0)
QT
4 tháng 3 2019 lúc 19:54

\(\frac{x+1}{9}+\frac{x+2}{8}=\frac{x+3}{7}+\frac{x+4}{6}\)

\(\Leftrightarrow\frac{x+1}{9}+1+\frac{x+2}{8}+1=\frac{x+3}{7}+1+\frac{x+4}{6}+1\)

\(\Leftrightarrow\frac{x+10}{9}+\frac{x+10}{8}-\frac{x+10}{7}-\frac{x+10}{6}=0\)

\(\left(x+10\right)\left(\frac{1}{9}+\frac{1}{8}-\frac{1}{7}-\frac{1}{6}\right)=0\)

\(\frac{1}{9}+\frac{1}{8}-\frac{1}{7}-\frac{1}{6}\ne0\)

nên => x+10 = 0

=> x= -10 

Bình luận (0)
BM
4 tháng 3 2019 lúc 20:00

dat x+1 la a

a/9+(a+1)/8=(a+2)/7+(a+3)/6

a/9+a/8+1/8=a/7+2/7+a/6+1/2

a/9+a/8-a/7-a/6=-1/8+2/7+1/2

a(1/9+1/8-1/7-1/6)=37/56

a.-37/504=37/56

a=-9

=> x=-10

thanks me later yup!!

Bình luận (0)