Are you in LACA? If so, please let me know :)
The answer is B because the Mechanical Reaper changed the way the world worked at the time; It made the demand for slaves go up as the work necessitated some manual work
y≈2/3x+4/3
As you have the paralel equation, you can have the pending from it by turning the equation to the form : y=mx+b, where m=2/3
3y=-6+2x
y=2/3x-(6/3) which is y=2/3x-2
from here you have m= 2/3
then to construct the equation you use the formula with the point (-2,0) which is y-y1= m (x-x1), where y1= 0 and x1=-2 and following the formula you have:
y-0= 2/3 (x-(-2)) which results into: y=2/3 (x+2) and you turn it into an explicit ecuation by multiplying y= 2/3x+4/3, this way you have y=mx+b equation formula