Sửa đề:
\(\dfrac{1+2y}{18}=\dfrac{1+4y}{24}=\dfrac{1+6y}{6x}.\)
Giải:
Ta có: \(\dfrac{1+2y}{18}=\dfrac{1+4y}{24}.\)
\(\Leftrightarrow\left(1+2y\right)24=18\left(1+4y\right).\)
\(\Leftrightarrow24+48y=18+72y.\)
\(\Leftrightarrow48y-72y=18-24.\)
\(\Leftrightarrow-24y=-6.\)
\(\Leftrightarrow y=\dfrac{-6}{-24}=\dfrac{1}{4}.\)
Thay \(y=\dfrac{1}{4}\) vào \(\dfrac{1+4y}{24}=\dfrac{1+6y}{6x}\), ta có:
\(\dfrac{1+4.\dfrac{1}{4}}{24}=\dfrac{1+6.\dfrac{1}{4}}{6x}.\)
\(\Rightarrow\dfrac{1+1}{24}=\dfrac{1+\dfrac{3}{2}}{6x}.\)
\(\Rightarrow\dfrac{2}{24}=\dfrac{2,5}{6x}.\)
\(\Rightarrow6x=\dfrac{24.2,5}{2}.\)
\(\Rightarrow6x=30.\)
\(\Rightarrow x=\dfrac{30}{6}=5.\)
Vậy \(x=5.\)
