
Felicia D. answered 06/15/20
STEM and SAT Reading, Writing, and Math Tutor
There are a couple ways to solve this problem: one way is to find the time t algebraically, and another way is to plug in the given answer choices for t, and see which answer choice gives you a tree height h closest to 32m.
If we were to solve this problem algebraically:
h(t) = 3.3t - 0.54, where h(t) = h = 32, and t = ?
32 = 3.3t - 0.54
32.54 = 3.3t
If you could use a calculator, you get: 9.86 = t
Without a calculator, you can estimate the expression "32.54 = 3.3t" as: 33 = 3t
and get t = 11 approximately.
Which gives D) 10 years as the correct answer.
If we plugged in the answer choices to get a value for t:
We can first plug in choice D, t = 10 years, because it's easy to work with.
h(t) = 3.3(10) - 0.54
h(t) = 33 - 0.54
h(t) = 32.45
Which is very close to the desired height h of 32m, giving choice D as the correct answer.