Answer:
g(x)=4x-48
Step-by-step explanation:
f(x)=0.25x + 12
substitute
f(x) with y
y=0.25x + 12
then replace x with y and y with x
x=0.25y + 12
swap equation
0.25y + 12 = x
0.25y = x - 12
divide both sides by 0.25
Y=4x-48
