Look at what is happening to the y-values between the two graphs.
From the y-value in f(x) going from 1 to -3 in g(x)
and the y-value in f(x) going from -1 to 3 in g(x)
Think: what is being multiplied by the f(x) value in order to obtain the g(x) value?
It is -3
Therefore g(x) = -3 • f(x)
k = -3
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