The second sentence expresses a relationship between the two unknowns, so we'll use it to write our first mathematical expression.

Boarding Kennel Problem

In a boarding kennel, dogs number 12 more than 2 times the number of cats. If there are 75 animals, how many cats are boarded?

Step 4: Set up strategy sentences. Use them to set up and solve mathematical equations.

•The number of cats plus the number of dogs is 75.

•The number of dogs is 12 more than 2 times the number of cats.

If c is the number of cats, how do we express the number of dogs?

A. 2c - 12

B. 2(c + 12)

C. 2c+12

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