The number of comic books is an illustration of a linear function
- The complete equations are:
and 
- The value of b has increased by 4
She had 17 comic books already.
So, we have:

Her order of 65 books contains 8 comic books per collection.
So, we have:


This is represented as:

So, we have:

Rewrite as:

Subtract 17 from both sides

Divide both sides by 8

Assume she has 97 books in her collection, then the equation would be represented as:

Subtract 17 from both sides

Divide both sides by 8

The values of b are 6 and 10.
The difference between 6 and 10 is 4
Hence, the value of b has increased by 4
Read more about linear equations at:
brainly.com/question/11897796