Rachel is selling T-shirts. It costs her $5 each week to advertise her T-shirts. She buys each T-shirt for $3.50 and sells each one for $8.00. Write an equation to model the amount of profit, P, she makes from selling x T-shirts in one week.

P = 3.50x − 5
P = 8x − 3.5
P = 5x + 3.5
P = 4.5x − 5