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Ch. 3 - Polynomial and Rational Functions
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 4, Problema 51

Write an equation in vertex form of the parabola that has the same shape as the graph of f(x) = 2x2 but with the given point as the vertex. (−10, −5)

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1
Recall that the vertex form of a parabola is given by the equation \(y = a(x - h)^2 + k\), where \((h, k)\) is the vertex of the parabola and \(a\) determines the shape (width and direction) of the parabola.
Identify the value of \(a\) from the original function \(f(x) = 2x^2\). Here, \(a = 2\), which means the parabola opens upward and is narrower than the standard parabola \(y = x^2\).
Use the given vertex point \((-10, -5)\) to substitute \(h = -10\) and \(k = -5\) into the vertex form equation, so it becomes \(y = 2(x - (-10))^2 + (-5)\).
Simplify the expression inside the parentheses: \(x - (-10)\) becomes \(x + 10\), so the equation is \(y = 2(x + 10)^2 - 5\).
This equation represents a parabola with the same shape as \(f(x) = 2x^2\) but shifted so that its vertex is at \((-10, -5)\).

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