HERE'S A QUESTION NEEDED FOR ANSWERING! In the equation y = 3x – 1, what is the value of y when x equals –3

Kayla made observations about the sellin price of a new brand of coffee that sold in the three different sized bags she recorded those observations in the following table 6 is $2.10 8 is $2.80 and 16 is to $5.60 use the relationship to predict the cost of a 20oz bag of coffee.