Big Ideas Math Algebra 2, 2014
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Big Ideas Math Algebra 2, 2014 View details
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Exercise 5 Page 20

Describe the parent function and then use slope to graph the functions.

Graph:

Transformation: A vertical stretch by a factor of 3.

Practice makes perfect

The given function is linear, so its parent function is y=x. We will start by graphing both functions in one coordinate plane. Then we will compare them to describe the transformation.

Graphing the Functions

To graph both of the functions, we will use their slopes and y-intercepts.

Function Slope-intercept form Slope y-intercept
y=x y= 1x+ 0 1 0
y=3x y= 3x+ 0 3 0
Now let's plot the functions! In both cases, start at the y-intercept and draw a line using the slope.

Comparing the Functions

Having drawn our functions, we can describe the transformation.

We see that each y-value is being multiplied by 3 and all points are being pulled away from the x-axis. This is a vertical stretch by a factor of 3.