OG详解-OG6 数学2 Q11

Choice D is correct. It’s given that the function f defined by f(t) = 14t+9 gives the estimated length, in inches, of a vine plant t months after Tavon purchased it. For a function defined by an equation of the form f(t) = mt+b, where m and b are constants, b represents the value of f(0), or the value of f(t) when the value of t is 0. Therefore, for the function defined by f(t) = 14t+9, 9 represents the value of f(t) when the value of t is 0. This means that 0 months after the vine plant was purchased, the estimated length of the vine plant was 9 inches. Therefore, the best interpretation of 9 in this context is the estimated length of the vine plant was 9 inches when Tavon purchased it.
Choice A is incorrect and may result from conceptual or calculation errors. Choice B is incorrect. The vine plant is expected to grow 14 inches, not 9 inches, each month. Choice C is incorrect and may result from conceptual or calculation errors.