PDF chapter test TRY NOW

Complete the following pattern.
 
\(9 - 1 = \)
 
\(98 - 21 = \)
 
\(987 - 321 = \)
 
\(9876 - 4321 = \)
 
\(98765 - 54321 = \)
 
What comes next? 
 
\(-\) \(=\)