Question

The following graph shows the relationship between cost and revenue for a manufacturer of lab coats.
A graph has coats on the x-axis and cost in dollars on the y-axis. The cost line goes through (0, 1600) and (900, 2900). The revenue line goes through (0, 0) and (900, 2900). The lines intersect at (900, 2900).
Which of the following pairs of equations best suits this graph?
Cost
1.5 n + 1,600
I
Cost
4.5 n + 1,600
II
Revenue
3.25 n
III
Revenue
5.75 n
IV

a.
I and III
b.
I and IV
c.
II and III
d.
II and IV

Answer 1

Compute slopes from the points.

Cost slope = (2900 − 1600)/900 = 1300/900 = 13/9 ≈ 1.444, so Cost ≈ 1.5n + 1600 (I) fits best.

Revenue slope = 2900/900 = 29/9 ≈ 3.222, so Revenue ≈ 3.25n (III) fits best.

Answer: a. I and III.