The equation for profit is income – cost:
Profit = Income – Cost
Let us say that x is the number of sold amount
Profit = 9 x – (25,000 + 4 x)
Profit = 5 x – 25,000
Breakeven point occurs when Profit = 0, hence:
5 x = 25,000
x = 5,000
The breakeven is when 5,000 people uses the income tax app