9.10.6 Vertex Form and Coordinates of the Vertex

Algebra 19.10.6 Vertex Form and Coordinates of the Vertex

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9.10.6 • Vertex Form and Coordinates of the Vertex

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A quadratic function is defined by the expression $x^{2} - 20 x + 19$ .

Rewrite the expression in vertex form (of a quadratic expression) and give the coordinates of the vertex (of a graph). Show your reasoning.

Compare your answer:

$(x - 10)^{2} - 81$ . The vertex is at $(10, - 81)$ .

$x^{2} - 20 x + 19$

$x^{2} - 20 x + 100 + 19 - 100$

$x^{2} - 20 x + 100 - 81$

$(x - 10)^{2} - 81$

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- Authors: Lynn Marecek, MaryAnne Anthony-Smith, Andrea Honeycutt Mathis, Jay Abramson, Sharon North, Amy Baldwin, Alyssa Howell
- Publisher/website: OpenStax
- Book title: Algebra 1
- Publication date: Jun 4, 2025
- Location: Houston, Texas
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- Section URL: https://openstax.org/books/algebra-1/pages/9-10-6-vertex-form-and-coordinates-of-the-vertex

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