We know that Jaydin reads 25 pages on the first day. On the second day, she reads 7 more pages than she read on the first day, which is 25 + 7 = 32 pages. On the third day, she reads 7 more pages than she read on the second day, which is 32 + 7 = 39 pages. We can see that the number of pages she reads each day is increasing by 7.
Therefore, the equation that represents the number of pages Jaydin will read on day n is:
y = 25 + 7(n - 1)
Simplifying the equation, we get:
y = 7n + 18
So, the equation that best represents the number of pages Jaydin will read on day n is y = 7n + 18.