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← Giving us the vertex - College Algebra

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Showing Revision 2 created 05/24/2016 by Udacity Robot.

  1. The answer is this one. Y minus k equals a times the quantity x minus h squared.
  2. This is almost the same as the equation that we were working with, in the last
  3. lesson. Remember that we kept talking about the form y minus k equals x minus h
  4. squared. And this was used for parabolas that had a leading coefficient of 1. So
  5. this makes perfect sense that if we have a leading coefficent of a instead of 1.
  6. We would modify the equation like this. Now, 2 of these equations here are
  7. actually not correct mathematical representations of what we're looking for.
  8. This one, y minus k equasl ax minus h. Doesn't graph a parabola at all. We can
  9. see that we only have an x to the first term, not an x to the second term. So
  10. this is a linear equation. That means it definitely can't be right. And the last
  11. one right here doesn't have the correct placement of the leading coefficient of
  12. a, as we can see from the last example we did. The second choice is
  13. mathematically equivalent to the third one, the correct one, except here, like
  14. we saw in the last quiz, we can't directly read off the coordinates of the
  15. vertex, or we wouldn't be able to if we had actual numbers plugged in. So this
  16. is the best choice.