3. Find two positive numbers x and y whose sum is 48 and their relation 5x2y + 10 is maximized. 6. Because of terrain difficulties, two sides of a fence can be built for $6 per ft, while the other two sides cost $4 per ft (see the sketch). Find the dimension of the field of maximum area that can be enclosed for $1200. a leos latty sill on hatrootin ed nowoubony blubile wead $6 per ft $4 per ft $6 per ft $4 per ft