Question 234657
Given that there was 36heads , the total number of chickens and cows will be 36.
so let the number of chickens be x and number of cows be y 


Equation 1 : x+y=36 


Equation 2 : 2x+4y=96 (for the total number of legs)


Solution :
Subst. x=36-y to Eqn2


2(36-y)+4y=96
72-2y+4y=96
2y=24
y=12

x= 36-12 = 24.


so there were 12cows and  24 chickens.