Answer: Choice A) -5
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Step-by-step explanation:
The point (-2,2) is on the red f(x) line. This point is marked in black.
It corresponds to the point (-2,-10) on the g(x) blue line.
The point (-2,2) moves to (-2,-10). The x coordinate stays at x = -2. The y coordinate has gone from y = 2 to y = -10. This is a jump of "times negative 5".
-5*2 = -10
So we see that k = -5
Saying g(x) = k*f(x) is the same as g(x) = -5*f(x)
Recall that y = f(x), so saying -5*f(x) is really saying "whatever the y coordinate is on f(x), multiply it by -5 to get the corresponding y coordinate on g(x)".