cats=c dogs=d
d+37=c
d+c=78
1. In the second equation, substitute c for d=37
d+d+37=78
2.Subtract 37 from both sides
d+d=41
3.Add like terms.
2d=41
4. To get d alone, you have two divide by 2
d=20.5
5. Now subtract 20.5 from 78 to get the number of cats.
78-20.5=57.5
number of cats=57.5
number of dogs=20.5
