A company’s daily profit P in pesos, is given by the equation P = -2x^2 + 120x - 800

A company’s daily profit P in pesos, is given by the equation P = -2x2 + 120x - 800 where x is the number of articles per day. Find x so that the daily profit is maximum.

A. 20 C. 40
B. 30 D. 50