Found this when I was doing my own work, hope this helps.
Answer:
Euler's Identity
Euler's Identity is written simply as: e^(iπ) + 1 = 0, it comprises the five most important mathematical constants, and it is an equation that has been compared to a Shakespearean sonnet.
Step-by-step explanation:
He would have to sell $20,000 worth of clothes to get $2,000