A farmer has ducks and cows they have 22 heads and 56 legs how much of each animal? I really don't get this :/

Answer 1

d has 2 legs
c has 4 legs
each has one head
so
d + c = 22
2d + 4c = 56 or d + 2c = 28

d + c = 22
d + 2c = 28
------------ subtract
0 - c = -6
c = 6
then d = 22-6 = 16