Since slope intercept is y=mx+b, you first want to get rid of the 2x by subtracting it from both sides. after, you should end up with 4y=16-2x or 4y=-2x+16, they both are the same, but some teachers might prefer the slope first. after that, you want to get the y alone, so you divide everything by 4. you should end up with the slope intercept form being y=-2/4x+4, simplified to y=-1/2x+4.
subtract r from c to get 8x+10
replace x with 3
8(3) +10 = 34 which in hundreds is 3400 dollars
the answer is C
The answer would be D. For you to find the solution you would need to look at the x from the coordinates.
A ) The domain:

x ≤ -4 and x≥ 4 or: x ∈ ( - ∞ , - 4 ) ∪ ( 4 , + ∞ )
b ) f ` ( x ) =

c ) The slope of the line normal to the graph at x = 5
m = -1 / f `(x)
f ` ( x ) =
m = - 3/34