There are 23 animals in the barn.Some are chickens and some are goats.There are 80 legs in all.How many of each animal is there?

Question

 graphing

Answer 1

C = # chickens

G = # goats

(1)  C + G = 23

As for legs:

(2)  2C + 4G = 80 (each C has 2 legs and each G has 4 legs)

Solving equation (1):  C = 23 - G

Substituting in equation (2)

2(23 - G) + 4G = 80

2G = 34

G = 17

C = 6

There are 17 goats and 6 chickens