Answer:
11 pigs.
6 chickens.
Step-by-step explanation:
Pigs have 4 legs while chickens have 2 legs. Also, pigs have just 1 head and the same for chickens.
Let pigs be X and let chickens be Y
For heads,
X + Y = 17
For legs,
4X + 2Y = 56
Solving both equations simultaneously,
4X + 2(17 - X) = 56
2X = 56 - 34
2X = 22
X = 11
So, Y = 17 - 11
= 6
There are 11 pigs and 6 chickens.