Big Ideas Math Algebra 1, 2015
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Big Ideas Math Algebra 1, 2015 View details
6. Transformations of Graphs of Linear Functions
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Exercise 27 Page 152

Make a table of values to find points from each graph.

The graph of h is a horizontal shrink of the graph of f by a factor of 15.

Practice makes perfect

First, let's use a table of values to find points on the graph of f(x)=-2 x-2.

x -2 x-2 f(x)
0 -2( 0)-2 -2
5 -2( 5)-2 -12
10 -2( 10)-2 -22
We can plot these points and connect them with a straight line to have the graph of f(x).

Now, let's look at how the function h(x)=f(5x) differs from f(x).

x -2 x - 2 f(x) f(5x) h(x)
0 -2( 0) - 2 -2 -2(5( 0))-2 -2
1 -2( 1) - 2 -4 -2(5( 1))-2 -12
2 -2( 2) - 2 -6 -2(5( 2))-2 -22

If we plot these points on the same coordinate plane as f(x), we can see that our points have been shrunk to be one fifth as far away from the y-axis as they were before.

Therefore, the graph of h is a horizontal shrink of the graph of f by a factor of 15.