Big Ideas Math Algebra 1, 2015
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Big Ideas Math Algebra 1, 2015 View details
Chapter Review
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Exercise 25 Page 167

Make a table of values for f, then write h in the form y=f(x-r).

Graph:

functions_graph

Transformation: The graph of h is a horizontal translation 3 units to the left from the graph of f.

Practice makes perfect

We are asked to graph f(x)=3x+4 and h(x)=f(x+3). Also, we need to find the transformations from the graph of f to the graph of h.

Graph of f(x)

To graph f(x), we will first make a table of values.

x 3x+4 f(x)
0 3( 0)+4 4
2 3( 2)+4 10
4 3( 4)+4 16

Now, we can plot these points and connect them with a straight line to have the graph of f(x).

graph_of_f

Graph of h(x)

Let's recall the definition of a horizontal translation. When subtracting a number r from a function's input before evaluating, the function translates the graph horizontally. y=f(x- r) A value of r less than 0 represents a shift of the original function to the left. Conversely, a value of r greater than 0 means a shift to the right. Because we are given h(x)=f(x+3), we can state that h is a horizontal translation of f. Let's rewrite h(x) to see the direction of the translation. h(x)=f(x+3) ⇕ h(x)=f(x-( -3)) In this case, r is -3. Since -3<0, h(x) is a horizontal translation 3 units to the left from the graph of f.

translation_graph