In this case, we'll have to carry out several steps to find the solution.
Step 01:
Data
p (x) = 15x - 2,500
p (x) = net profit ($)
x = number of t-shirts
Step 02:
1. y - intercept
x = 0
y = 15x - 2500
y = 15(0) - 2500
y = -2500
( 0 , -2500)
Step 03:
The y-intercept means that if you don't sell any T-shirts, there will be a loss of $ 2,500.
Step 04:
p(x) >0
15x - 2500 > 0
15x -2500 + 2500 > 2500
15x > 2500
15x / 15 > 2500 / 15
x > 166.67
More than 167 t-shirts must be sold to make a profit.
That is the full solution.