To solve for the number of unread books remaining on Alex's bookshelf after 9 months of consistent reading, we need to use the given function [tex]\( b(t) \)[/tex]. The function is defined as:
[tex]\[ b(t) = 75 - 5t \][/tex]
Let's break down the steps:
1. Identify the function: [tex]\( b(t) = 75 - 5t \)[/tex].
2. Substitute [tex]\( t = 9 \)[/tex] into the function:
[tex]\[ b(9) = 75 - 5 \times 9 \][/tex]
3. Perform the multiplication:
[tex]\[ 5 \times 9 = 45 \][/tex]
4. Subtract the result from 75:
[tex]\[ 75 - 45 = 30 \][/tex]
Therefore, [tex]\( b(9) = 30 \)[/tex].
This means that the number of unread books remaining on Alex's bookshelf after 9 months is 30.
Let’s fill in the missing parts:
[tex]\[ b(9) = 30 \][/tex]
This means that [tex]\( b(t) = 75 - 5t \)[/tex].