Your graphing calculator is a great tool! Get comfortable with it and it will save you lots of time and effort.
To perform a linear regression:
1) Go to the home screen (on).
2) Select "Lists and Spreadsheets"
3) Enter your x-values in column A and your y-values in column B.
4) Scroll to the very top of the A value to highlight the column. Then press "shift" and highlight the B values.
5) Select "Menu", "Statistics", "Stat Calculation", "Linear Regression (mx+b)"
Use the equation you are given to make predictions!