Profitable Business Charles buys factory reconditioned hedge trimmers for $40 each and sel...

Profitable Business Charles buys factory reconditioned hedge trimmers for $40 each and sells them on Ebay for $68 each. He has a fixed cost of $200 per month. If x is the number of hedge trimmers he sells per month, then his revenue and cost (in dollars) are given by R(x) = 68x and C(x) = 40x + 200. Find a fonnula for the function P(x) = R(x) − C(x). For what values of x is his profit positive?