Question

There are 18 animals in the farm. Some are chickens and some are cows. I counted 50 legs in all. How many of the animals are cows and how many are chickens?

k+c=18
2k+4c=50

Can someone help me to finish the problem? Thanks.

Answer 1

k+c=18
2k+4c=50

k = 18 - c

2(18 - c) + 4c = 50

36 - 2c + 4c = 50

2c = 14

c = 7

Answer 2

You just have to make a system of equations and use it to find the solution:
x+y=18 -4x-4y=-72 y=-22/-2 y=11 x+11=18 x=7
4x+2y=50 +4x+2y=50
-2y=-22
I hope it will help :)