Answer:
4 ducks and 5 cows
Step-by-step explanation:
Lets assume that there are x number of ducks.
Since there are a total of 9 animals,
then, there must be (9 - x) number of cows.
Each duck has 2 legs and each cow has 4 legs.
So the total number of legs will be 2x + 4(9 - x).
We are told that there are 28 legs.
Therefore,
2x + 4(9 - x) = 28
2x + 36 - 4x = 28
- 2x = - 8
x = 4
ducks = 4
cows = 9 - 4 = 5
