Online sellers spent P300.00 in producing 100 pcs. facemasks and will sell it for P10.00 each. If the seller sold 80 facemasks, how much money did he/she make?

Find the directions in which the function increases and decreases most rapidly at upper p 0p0. then find the derivatives of the function in these directions. f(x,y)equals=x squared plus xy plus y squaredx2+xy+y2, upper p 0p0left parenthesis 1 comma negative 4 right parenthesis