Mathematics
Grade 9
15 min
Transformations of absolute value functions
Transformations of absolute value functions
Tutorial Preview
1
Introduction & Learning Objectives
Learning Objectives
Identify the parameters a, h, and k in the function g(x) = a|x - h| + k.
Describe the effect of each parameter (a, h, k) on the graph of the parent function f(x) = |x|.
Graph a transformed absolute value function using its vertex and the value of 'a'.
Write the equation of a transformed absolute value function given its graph.
Determine the vertex, axis of symmetry, domain, and range of a transformed absolute value function.
Compare the properties of a transformed function to the parent function f(x) = |x|.
Have you ever noticed how a bouncing ball's path can look like a 'V' shape? 🏀 We can describe that path perfectly using math!
In this tutorial, you will learn how to take the basic V-shaped graph of y = |x| and move it, flip...
2
Key Concepts & Vocabulary
TermDefinitionExample
Parent FunctionThe simplest form of a function in a family. For absolute value functions, the parent function is f(x) = |x|.The graph of f(x) = |x| is a V-shape with its vertex at the origin (0, 0) and sides with slopes of 1 and -1.
TransformationA change made to a function's graph, affecting its position, shape, or orientation.Shifting the graph of y = |x| two units to the right to get y = |x - 2| is a transformation.
TranslationA transformation that 'slides' a graph horizontally (left or right) or vertically (up or down) without changing its shape or orientation.The graph of y = |x| + 3 is a vertical translation of the parent function 3 units up.
DilationA transformation that stretches or compresses a graph, making it narrower or wider. It is control...
3
Core Formulas
The Transformation Formula
g(x) = a|x - h| + k
This is the general form for a transformed absolute value function, where 'a', 'h', and 'k' are parameters that control the transformations applied to the parent function f(x) = |x|.
Parameter 'a': Dilation and Reflection
If |a| > 1, the graph is vertically stretched (narrower).
If 0 < |a| < 1, the graph is vertically compressed (wider).
If a < 0, the graph is reflected across the x-axis.
The 'a' value multiplies the output of the absolute value. It controls the steepness of the V-shape and whether it opens up or down.
Parameters 'h' and 'k': Translations
The vertex of the graph is at the point (h, k).
'h' controls the horizontal sh...
4 more steps in this tutorial
Sign up free to access the complete tutorial with worked examples and practice.
Sign Up Free to ContinueSample Practice Questions
Challenging
The graph of an absolute value function has a vertex at (-2, 5) and passes through the point (0, 1). What is the value of this function when x = 3?
A.1
B.-10
C.0
D.-5
Challenging
The graph of g(x) = a|x - h| + k has its vertex in Quadrant IV and is narrower than f(x) = |x|. Which of the following must be true about the parameters?
A.a < -1, h < 0, k > 0
B.a > 1, h > 0, k < 0
C.0 < a < 1, h > 0, k < 0
D.a > 1, h < 0, k < 0
Challenging
An absolute value function has a range of [4, ∞) and an axis of symmetry at x = -1. Which of the following could be its equation?
A.g(x) = -2|x - 1| + 4
B.g(x) = |x + 1| - 4
C.g(x) = 2|x + 1| + 4
D.g(x) = 2|x - 4| - 1
Want to practice and check your answers?
Sign up to access all questions with instant feedback, explanations, and progress tracking.
Start Practicing Free