Answer:
There 11 cows and 6 ducks in the meadow.
Explanation:
Given,
Total number of legs = 56
Total number of heads = 17
Solution,
Let the number of cows be 'c'.
And also let the number of ducks be 'd'.
We know that all the animals have 1 head.
So we can say that the total number of heads is equal to number of number of cows and number of ducks.
we can frame it as;

Again we know that cows have four legs and ducks have two legs.
So total number of legs is equal to number of cows multiplied by 4 plus number of ducks multiplied by 2.
framing in equation form, we get;

On dividing both side by '2' using division property, we get;

Now Subtracting equation 1 from equation 2 we get;

Substituting the value of c in equation 1 we get;

Hence There 11 cows and 6 ducks in the meadow.