Question

At a pet store, it costs $5 to wash a cat and $7.50 to wash a dog. Last week the store made $60 from washing cats and dogs. If 6 cats were washed, write and solve a linear equation to find how many dogs were washed.

Answer 1

If you let x equal the number of cats washed and y equal the number of dogs washed then you can make the equation:
5x+7.5y=60
You can then put the number of cats washed into the equation:
5(6)+7.5y=60
30+7.5y=60
7.5y=30
y=4
So 4 dogs were washed