Answer:
k = -3
Explanation:
f(x) has a slope of 1, and g(x) has a slope of -3, so to get to g(x) from f(x) you would have to multiply it by -3. We need to check the true functions to be sure, though.
The true function for f(x) is f(x) = x + 4.
The true function for g(x) is g(x) = -3x - 12.
g(x) = -3*f(x)