Big Ideas Math Algebra 2, 2014
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Big Ideas Math Algebra 2, 2014 View details
1. Transformations of Quadratic Functions
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Exercise 23 Page 52

Start with a vertical shrink.

Transformations:A vertical shrink by a factor of 15 followed by a vertical translation 4 units down.
Graph:

Practice makes perfect

We want to describe how to transform the parent function y=x^2 to the graph of the given quadratic function. y=1/5x^2-4 To do so, we need to consider two possible transformations.

  1. Vertical stretches and shrinks
  2. Vertical translations

    Let's consider them one at the time.

    Vertical Stretch or Shrink

    We have a vertical stretch when x^2 is multiplied by a number greater than one. If x^2 is multiplied by a number less than one, a vertical shrink will take place.
    In the given exercise, x^2 is multiplied by 15. Therefore, the graph of f will be vertically shrunk by a factor of 15.

    Vertical Translation

    If an addition or subtraction is applied to the whole function, the graph will be vertically translated. In the case of addition, the graph will be translated up. In the case of subtraction, it will be moved downwards. In the given equation, 4 is subtracted from the whole function, so the previous graph will be translated 4 units down.

    Final Graph

    Let's now graph the given function and the parent function f(x)=x^2 on the same coordinate grid.

    Finally, let's summarize all the transformations of the graph of f.

    • A vertical shrink by a factor of 15
    • A vertical translation 4 units down