Example 3

Write a quadratic equation in one variable that is true for the three data points (0, 0), (1, 2), and (2, 8) by solving a system of three equations based on the standard form of a quadratic equation, . Then, use your equation to find the -value for a fourth point on the same graph that has an -value of 3.
  1. Use the given data points to write three equations using the standard form of a quadratic equation.
  2. Examine the resulting equations for any common traits that can be used to simplify them.
  3. Use the results to solve for another variable.
  4. Use the values determined for , , and to write the quadratic equation that is true for the three data points.
  5. Use the resulting quadratic equation model for the three given points to predict the location of a fourth point for which .
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