(18-2x)10- 3= 1021
\(\Rightarrow\) (18-2x)10 = 1024
\(\Leftrightarrow\) (18-2x)10 = 210
\(\Rightarrow\) 18-2x = 2
\(\Rightarrow\) 2x = 16
\(\Rightarrow\) x = 8
<=> (1810 - 2x10) - 3 = 1021
= > 2x10 = 1021 - 3 + 1810
=> 2x10 = 1018 + 3570467226624
=> 2x10 = 3570467227642