a) \(x+9,44=18,36\)
\(\Leftrightarrow x=18,36-9,44\)
\(\Leftrightarrow x=8,92\)
b) \(2012\div x+23=526\)
\(\Leftrightarrow2012\div x+23=526\)
\(\Leftrightarrow2012\div x=526-23\)
\(\Leftrightarrow2012=503\times x\)
\(\Leftrightarrow x=2012\div503\)
\(\Leftrightarrow x=4\)