Answer: 19 birds were at the shelter on Wednesday.
Step-by-step explanation:
Let x represent the number of birds that were at the shelter on Wednesday.
Let y represent the number of birds that were at the shelter on Wednesday.
Nicole found a record showing that there were a total of 40 birds and cats on Wednesday. This means that
x + y = 40
The animal shelter spends $5.50 per day to care for each bird and $8.50 per day to care for each cat. Nicole noticed that the shelter spent $283.00 caring for birds and cats on Wednesday. This means that
5.5x + 8.5y = 283 - - - - - - - - - - - - - -1
Substituting x = 40 - y into equation 1, it becomes
5.5(40 - y) + 8.5y = 283
220 - 5.5y + 8.5y = 283
- 5.5y + 8.5y = 283 - 220
3y = 63
y = 63/3 = 21
x = 40 - y = 40 - 21
x = 19
