equation word problem

Question

In a country the number of students who completed high school and enrolled in college that same year increased from 1.4 million in 2002 to 1.9 million in 2006.
a) Find an equation for the line including the given data points. Let x represent the number of years after 2000 and y the number of recent high school graduates (or the equivalent) who enrolled in college that year.
b) Estimate the number of high school graduates (or the equivalent) who enrolled in college in 2003 and in 2013
.

Answer 1

Jessica, we need first to find the slope, the change in output over the change in input.

 

(1.9 million - 1.4 million)/(6 - 2) = 500,000/4 = 125,000

 

(y - y₁) = m(x - x₁)

y - 1.4 million = 125,000(x - 4)

y - 1.4 million = 125,000x - 500,000

y = 125,000x + 900,000

 

y = 125,000(3) + 900,000

y = 375,000 + 900,000

y = 1.275 million

 

y = 125,000(13) + 900,000

y = 1.625 million + 0.9 million = 2.525 million