a Subtract the equations for the number who flew from the total.
B
b Use the answer from Part A, with n equal to the number of years 2012 is from 1995.
C
c Use the equation for total students, with n equal to the number of years 2015 is from 1995.
A
a D=6n+14
B
b 116 thousand
C
c 301 thousand
Practice makes perfect
a We need to work with the equations related to the number of students who drive or fly to their destinations for spring break. We are given equations for the total number of students, T, and those who flew F. Let's write a model for finding the number of students who drive, D.
D = T - F
With that model in mind, we can substitute the given expressions and simplify the polynomial.
The equation model for the number of students who drove to their destination is D=6n+14.
b For this part, we will use our solution from Part A to determine the number of students who drove in 2012. First, we need to find how many years are between 1995 and 2012. We can do this by subtracting.
2012-1995=17
Now, we can substitute n=17 into our model for the number of drivers.
The number of drivers the model predicts for 2012 is 116 thousand.
c For this part of the exercise, we will treat it similarly to how we solved Part B, but instead use the equation for the total number of students. First, let's find out how many years are between 1995 and 2015.
2015-1995=20
Now, let's substitute n=20 into the equation for the total number of students.
