Would you please help me understand the steps for this problem?

This is how we were tought to do these problems (just for your reference).

of type A firm produces two types of earphones, per month x thars and of type A and y thousand of B If the revenue and cost equations for month are (in millions of dollars) R(x,y) = 2x+3y. and C(x, y) = x - 2xy +2yt6x-eyrs, determice be produced per month to maximize profit, what is the maximum profit? (Hint & P=R-C) 1 m(x, y, z) = x y 4 x taya Vex y z 2125 my, y = xy + 4x m (x,y) = xy + By mwy = xy + Sooy + 250x mx=y=250x 20 x Sone for y= 250x 500 20 & - 250 mx=y- y =0 250 (S0 2 15out 500 Sooy - 2004420 y (2002-2004 3 =0 ? 20043 Sool or 5002 900 x = 10 za (10) 15) = 2.5 Sint 10 nx 2.5in