Answer:
The linear equation that represent this problem is

Explanation:
Let
x -----> the number of people
y ----> the profit in dollars
we have
For x=100, y=2,500
and
For x=80, y=1,500
Find the slope m
we have
(80,1,500) and (100,2,500)
The slope is equal to

Find the equation of the line into point slope form

we have
and point (100,2,500)
substitute
----> equation in slope point form
Convert to slope intercept form

