S A band is selling concert shirts on their website. If they charge $15 a shirt, they sell 550 shirts in one month.
The monthly cost for the shirts is $1500. The band manager estimates that for every $2 increase in price they
will sell 20 less shirts a month. The monthly profit for the band selling shirts can be modeled with the equation
P(x)=(15+2x)(550 – 20x) –1500, where x represents the number of $2 price increases. Use technology to
graph the profit equation and determine the number of shirts the band needs to see in a month to maximize
their profits.