To express Willow's reading in the form of a linear equation, we can define the following variables:
- Let \( t \) represent the time in minutes that Willow spends reading.
- Let \( p \) represent the page number she is on after \( t \) minutes.
Since Willow starts on page 15 and reads 2 pages every minute, we can describe her reading with the following equation:
\[ p = 2t + 15 \]
In this equation:
- The term \( 2t \) represents the total number of pages she reads after \( t \) minutes.
- The constant \( 15 \) represents the starting page.
So, the linear equation showing how the page number \( p \) changes with time \( t \) is \( p = 2t + 15 \).