Answer:
He did not add 12 to 36.
Step-by-step explanation:
First, let's solve the equation correctly:
[tex]\begin{gathered} 12+x=36 \\ \rightarrow x=36-12 \\ \rightarrow x=24 \end{gathered}[/tex]This way, we can conlcude that Skyler did not add 12 to 36, as he said he would.