\(x\times64-43\times x-x=1200\)
\(x\times64-43\times x-x\times1=1200\)
\(x\times\left(64-43-1\right)=1200\)
\(x\times20=1200\)
\(x=1200:20\)
\(x=60\)
\(x\times64-43\times x-x=1200\)
\(\Rightarrow x\times64-43\times x-x\times1=1200\)
\(\Rightarrow x\times\left(64-43-1\right)=1200\)
\(\Rightarrow x\times20=1200\)
\(\Rightarrow x=1200\div20\)
\(\Rightarrow x=60\)