1. The problem statement, all variables and given/known data Hello! Here is the problem from Stitz-Zeager Pre-calculus book: At 9 PM, the temperature was 60F; at midnight, the temperature was 50F; and at 6 AM, the temperature was 70F . Use the technique in Example 8.2.3 to t a quadratic function to these data with the temperature, T, measured in degrees Fahrenheit, as the dependent variable, and the number of hours after 9 PM, t, measured in hours, as the independent variable. What was the coldest temperature of the night? When did it occur? 2. Relevant equations 3. The attempt at a solution My question is about the number of hours as undependable variable: do you think authors mean x1=9, x2=3, x3=9 by saying "the number of hours after 9PM"? Or do you think it should be x1=9, x2=0, x3=6, or x1=9, x2=12, x3=6? I am confused :) Thank you!