Answer:
28
Step-by-step explanation:
1) subtract 12 from both sides
2) divide by negative 1
slope intercept form is: y = mx + b
m = slope
b = y-intercept
In the equation y = 1/4x + 8
m = 1/4 = slope
b = 8 = y-intercept
When you derive a function from another using the transformation

you're translating the graph of the parent function f(x) horizontally.
More specifically, you translate the graph k units to the left if k is positive, k units to the right if k in negative.
So, starting from the graph of f(x), you have that the graph of

is the same graph of f(x), but shifted 3 units to the left.