Let uncle Wang plant x mu of eggplant and y mu of tomatoes;

x+y=25

1700x+ 1800y=44000

Namely:

17x+ 17y = 25 * 17

17x+ 18y=440

Solve the equation:

x= 10，y = 15；

Uncle Wang got a total net profit:

2250x+2400y = 2250 *10+2400 *15 = 58500 (yuan).