McGraw Hill Integrated II, 2012
MH
McGraw Hill Integrated II, 2012 View details
Mid-Chapter Quiz
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Exercise 21 Page 132

Start with a reflection across the x-axis.

Transformations: Reflection across the x-axis, vertical compression by a factor of 58
Graph:

We want to describe how to transform the parent function f(x)=x^2 to the graph of the given quadratic function. h(x)=-5/8x^2 To do so, we need to consider four possible transformations.

  1. Reflections
  2. Stretches and compressions
  3. Horizontal translations
  4. Vertical translations

    Notice that we only need to consider the first and the second transformation.

    Reflection

    Whenever x^2 is multiplied by a negative number, we will start by reflecting the graph across the x-axis.
    If x^2 is being multiplied by a negative number, the above still applies but everything will be upside down. In the given exercise, x^2 is multiplied by - 58. Therefore, the previous graph will be vertically compressed by a factor of 58.

    Final Graph

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

    Finally, let's summarize how to draw the graph of the given function when starting with the parent function, f(x)=x^2.

    • Reflection across the x-axis
    • Vertical compression by a scale factor of 58