Metro Department Store's annual sales (in millions of dollars) during 5 years were Plot the annual sales (y) versus the year (x) and draw a straight line L through the points corresponding to the first and fifth years and derive an equation of the line L.
A)
B)
C)

Question

Metro Department Store's annual sales (in millions of dollars) during 5 years were  Plot the annual sales (y) versus the year (x) and draw a straight line L through the points corresponding to the first and fifth years and derive an equation of the line L.
A) ​ 
B) ​ 
C) ​

Quizplus · Accepted Answer

We plot the given data and draw a straight line passing through the points corresponding to the first and fifth years:

Year (x)     Sales (y)
1            11
2            eab
3            448
4            e894
5            2830

Using these two points, the slope of the line is:

m = (2830 - 11) / (5 - 1) = 704.75

Using the point-slope form of a line:

y - y1 = m(x - x1)

where (x1, y1) = (1, 11)

we get:

y - 11 = 704.75(x - 1)

Simplifying this equation, we get:

y = 704.75x - 693.75

Therefore, the best choice is B, which corresponds to the equation:

y = 704.75x - 693.75

Metro Department Store's Annual Sales (In Millions of Dollars) During