\(\frac{x-18}{74}+\frac{x-20}{72}+\frac{x-22}{70}=3\)
\(\Leftrightarrow\)\(\left(\frac{x-18}{74}-1\right)+\left(\frac{x-20}{72}-1\right)+\left(\frac{x-22}{70}-1\right)=0\)
\(\Leftrightarrow\)\(\frac{x-92}{74}+\frac{x-92}{72}+\frac{x-92}{70}=0\)
\(\Leftrightarrow\)\(\left(x-92\right)\left(\frac{1}{74}+\frac{1}{72}+\frac{1}{70}\right)=0\)
Mà \(\frac{1}{74}+\frac{1}{72}+\frac{1}{70}\ne0\)
\(\Leftrightarrow\)\(x+92=0\)
\(\Leftrightarrow\)\(x=-92\)
Vậy S = { - 92 }
Ta có :
\(\frac{x-18}{74}+\frac{x-20}{72}+\frac{x-22}{70}=3\)
\(\Leftrightarrow\)\(\left(\frac{x-18}{74}-1\right)+\left(\frac{x-20}{72}-1\right)+\left(\frac{x-22}{70}-1\right)=3-3\)
\(\Leftrightarrow\)\(\frac{x-92}{74}+\frac{x-92}{72}+\frac{x-92}{70}=0\)
\(\Leftrightarrow\)\(\left(x-92\right)\left(\frac{1}{74}+\frac{1}{72}+\frac{1}{70}\right)=0\)
Vì \(\frac{1}{74}+\frac{1}{72}+\frac{1}{70}\ne0\)
\(\Rightarrow\)\(x-92=0\)
\(x=92\)
Vậy \(x=92\)
Chúc bạn học tốt
Ta có
\(\frac{x-18}{74}+\frac{x-20}{72}+\frac{x-22}{70}=3\)
<=> \(\left(\frac{x-18}{74}-1\right)+\left(\frac{x-20}{72}-1\right)+\left(\frac{x-22}{70}-1\right)=0\)
<=> \(\frac{x-92}{74}+\frac{x-92}{72}+\frac{x-92}{70}=0\)
<=> \(\left(x-92\right)\left(\frac{1}{74}+\frac{1}{72}+\frac{1}{70}\right)=0\)
Mà \(\frac{1}{74}+\frac{1}{72}+\frac{1}{70}\ne0\)nên x-92=0
=> x=92
\(\frac{x-18}{74}+\frac{x-20}{72}+\frac{x-22}{70}=3\)
\(\Rightarrow\left(\frac{x-18}{74}-1\right)+\left(\frac{x-20}{72}-1\right)+\left(\frac{x-22}{70}-1\right)=0\)
\(\frac{x-18-74}{74}+\frac{x-20-72}{72}+\frac{x-22-70}{70}=0\)
\(\frac{x-92}{74}+\frac{x-92}{72}+\frac{x-92}{70}=0\)
\(\left(x-92\right)\left(\frac{1}{74}+\frac{1}{72}+\frac{1}{70}\right)=0\)
\(\Leftrightarrow x-92=0\)
\(x=92\)
-92 chứ sao!!!!!!!!!!!!!!!!!!!!!!!$$$$$$$$$$$$$$%%%%%%%%%%%