Answer:
15 days
Step-by-step explanation:
The height of the sunflower is a function of time; the flower grows 4 cm per day. The constant of proportionality is thus (4 cm) / (1 day), or 4 cm/day.
The equation relating height to days is thus:
h(d) = (4 cm/day)d, where h is the height in cm and d is the number of days that have passed by.
When (after how many days) will the sunflower have grown to be 60 cm tall?
Solve h(d) =(4 cm/day)d for the number of days, d:
Let h(d) = 60 cm = (4 cm/day)d.
Dividing both sides of 60 cm = (4 cm/day)d by (4 cm/day), we get:
60 cm
--------------- = 15 days (answer)
4 cm/day