Final answer:
The expression f-1(26)=9 means that when the height of the plant is 26 inches, it took 9 days for the plant to reach that height.
Step-by-step explanation:
In this scenario, the function f(d) represents the height of a plant in inches, where d is the number of days since it was planted. The function f(d)=8+2d indicates that the height of the plant increases by 2 inches per day.
To interpret the meaning of f-1(26)=9, we need to find the inverse function of f(d) and understand its significance.
The inverse function of f(d)=8+2d is f-1(x)=(x-8)/2. This means that given a height value x, we can use the inverse function to find the number of days it took for the plant to reach that height.
Now, let's interpret f-1(26)=9. It means that when the height of the plant is 26 inches, it took 9 days for the plant to reach that height.