Answer:
The equation of the sunflower's height is h = 18+2.5w
Since the number 18 remains constant regardless of the change in number of weeks, we know that at the start h (w=0) = 18 + 2.5 x 0.
This means that, when Jin planted the sunflower, the sunflower's height was already 18 inches.
For such a reason, we can conclude that the number 18 could represent the sunflower's height at the start (original height).
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