Jada has $18 to spend at a gas station for snacks for her friends. A bag of Takis costs $1.50 and a slice of pizza costs $2. Complete the table showing three different combinations of Takis and pizza slices that Jada could have purchased for a total of $18. After completing the table, write an equation relating the number of bags of Takis t and the number pizza slices p that Jada could have purchased for a total of $18.​