Emma sells jewelry online. She has found that when she sells each piece of jewelry for $20, she sells an average of 23 pieces of jewelry every month. Emma has also found out that when she increases the price of jewelry by $5, the number of pieces sold per month decreases by an average of 7.

Emma's profit per month is given by the polynomial below, where x is the number of $5 increases in jewelry price over $20.

P(x) = $460 - $25x - $35x2