Im just. Learning this and I don’t know what to do

Given:
[tex]L||M[/tex]Therefore,
[tex]x+5=2x-7[/tex]Solve for x
Collect like terms
[tex]5+7=2x-x[/tex]Simplify
[tex]\begin{gathered} 12=x \\ \therefore x=12 \end{gathered}[/tex]Hence,
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