Lin working
[tex]\begin{gathered} 8d=2d \\ \text{divide both sides 2d} \\ \frac{8d}{2d}=\frac{2d}{2d} \\ 4=1 \end{gathered}[/tex]
Elena working
[tex]\begin{gathered} 8d=2d \\ \text{subtract 2d from both sides} \\ 8d-2d=2d-2d \\ 6d=0 \\ d=0 \end{gathered}[/tex]
Elena moves will lead to a solution of d which will be equals to zero . Lin working will definitely cancel d on both sides and lead to no solution .
