Since we are given two ordered pairs or points, therefore we can use the point-slope formula to create the linear model.
The general equation is in the form of:
y = mx + b
where m is the slope and b is the y-intercept
The slope can be calculated as:
m = (y2 – y1) / (x2 – x1)
m = (12.4 – 14.2) / (2000 – 1990)
m = -0.18
SO:
y = -0.18x + b
Choosing any ordered pair to calculate for b:
12.4 = -0.18(2000) + b
b = 372.4
Hence,
y = -0.18x + 372.4
