Chapter 7.3, Problem 3MP

Matched Problem 3 Repeat Example 3 with

     $P\left(x,y\right)=-66x^2+132xy-99y^2+132x–66y–19$

EXAMPLE 3 Profit Suppose that the surfboard company discussed earlier has developed the yearly profit equation

     $P\left(x,y\right)=-22x^2+22xy-11y^2+110x-44y-23$

where x is the number (in thousands) of standard surfboards produced per year, y is the number (in thousands) of competition surfboards produced per year, and P is profit (in thousands of dollars). How many of each type of board should be produced per year to realize a maximum profit? What is the maximum profit?