## Graphing Problem: given y = f(x), draw y = 3f(-x)

Quadratic equations and inequalities, variation equations, function notation, systems of equations, etc.
Notamathperson
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### Graphing Problem: given y = f(x), draw y = 3f(-x)

I am having trouble recalling what to do if a graph is multiplied. For example, y=f(x). Draw the graph of y=3f(-x). I am not sure how to start it.

stapel_eliz
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I am having trouble recalling what to do if a graph is multiplied.
In general, if the function is multiplied by a number $a$ with $|a|\, >\, 1$, then the graph gets "taller" or "skinnier"; otherwise, it gets "shorter" or fatter. When $a$ is negative, the graph flips upside-down.

Notamathperson
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### Re: Graphing Problem: given y = f(x), draw y = 3f(-x)

The problem is, the graph of the function is given in coordinates. For example, (0,1), (1,1), (2,1), (3, .5), (4,0). That is f(x). I am not sure what how to find the coordinates when the function is 3f(-x).

stapel_eliz
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Follow the instructions and examples provided in the lesson: To graph f(-x), find the corresponding point for f(x); then multiply the y-value by 3, and plot the point for that x-value. For instance, if they'd given you f(5) = 6, then f(-5) would be found by multiplying 6 by 3.