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Algebra 1

9.8.5 Lesson Summary

Algebra 19.8.5 Lesson Summary

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In this lesson, you learned how to:

  • Explain the steps and complete some missing steps for deriving the quadratic formula.
  • Explain how the quadratic formula is related to the process of completing the square for a quadratic equation ax2+bx+c=0ax2+bx+c=0.

Here are the activities that helped you reach those goals:

  • 9.8.1: Deriving the Quadratic Formula, Part 1
    • In this activity, you learned how to derive the quadratic formula by completing the square for a quadratic equation without evaluating some of the numerical expressions along the way.
    • 9.8.1: Self Check
    • 9.8.1: Additional Resources
  • 9.8.2: Deriving the Quadratic Formula, Part 2
    • In this activity, you studied a series of steps to solve ax2+bx+c=0ax2+bx+c=0 by completing the square and making sense of how it leads to the quadratic formula.
    • 9.8.2: Self Check
    • 9.8.2: Additional Resources
  • 9.8.3: Understanding That the Quadratic Formula Is the Combined Steps of Completing the Square
    • In this activity, you had to explain parts of a solution for solving an equation by completing the square, where each step was shown, but numerical expressions were not evaluated.

After these activities, you completed the following practice:

  • 9.8.4: Practice

Checking In

On a scale of 1 to 5, how confident do you feel about the learning goals of this lesson?

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