Combining Translations, Reflections, and Stretches

  • y = af(b(x - h)) + k
  • "a" is vertical stretch
  • "b" is horizontal stretch
  • "h" is horizontal shift
  • "k" is vertical shift
  • when y = f(x) becomes y = af(b(x - h)) + k, (x, y) becomes ((1/b)x + h, ay + k)


Sketching the Graph of a Transformed Function Example #1

  • use the equation to recognize the transformations y = af(b(x - h)) + k
  • choose multiple points to transform, (x, y) becomes ((1/b)x + h, ay + k)
  • plot new points and connect them


Sketching the Graph of a Transformed Function Example #2


Sketching the Graph of a Transformed Function Example #3


Sketching the Graph of a Transformed Function Example #4


Sketching the Graph of a Transformed Function Example #5


Sketching the Graph of a Transformed Function Example #6


Finding the Equation of a Transformed Function

  • in y = af(b(x - h)) + k, find the value of "a", "b", "h", and "k"
  • compare graphs to see if there has been any reflections (meaning "a" or "b" is negative)
  • compare the width of one section on the original function with the width of the same section on the transformed function
    • b = new width/old width
  • compare the height of one section on the original function with the height of the same section on the transformed function
    • a = new height/old height
  • choose one point to transform using the horizontal and vertical stretches and reflections, find the shifts required to reach the transformed point
    • h = horizontal distance to point
    • k = vertical distance to point

Complete and Continue