Answer: 52
Explanation:
The key thing to focus on is the phrasing "starting at the age of 8"
Specifically, your teacher wants the starting height when Mia was 8 years old. That height being 52 inches.
The 7 inches refers to how much she had grown over the 2 years, which is part of the rate of change (and will be part of the slope).
Side note: 52 inches = 4 ft, 4 inches
