# There are 40 cows and chicken in the farmyard. One quiet afternoon, Lack counted and found that there were 100 legs in all. How many cows and how many chickens are there?

##### 1 Answer

30 Chickens and 10 Cows

#### Explanation:

To help Lack determine how many cows and chickens are on his farm, we can use a system of equations using variables for Chickens and Cows.

Make

Cows =

Chickens =

So

For the legs we can make

Cows Legs =

Chicken Legs =

So

We can plug the value for

Distribute the 4 to the parenthesis

Combine like terms

Use additive inverse to isolate the variable value

Use multiplicative inverse to solve for the variable