It's known that
When two lines are parallel, their slopes are identical.
The slope between any two points can be calculated using the following formula:

We will calculate the slope for each case to find the solution to the problem.
Case A) Point 
Determine the slope of BC
Insert the values into the formula:



Thus,
The equation
is parallel to the line that goes through the points 
Therefore,
the result for Part A) is
------> 
Case B) Point 
Calculate the slope of DE
Plug the values into the formula:



Thus,
The equation
is parallel to the line that goes through the points 
Therefore,
the result for Part B) is
------> 
Case C) Point 
Determine the slope of FG
Insert the values into the formula:


Thus,
Any linear equation with slope
will be parallel to the line through the points 
Case D) Point 
Calculate the slope of HI
Substitute the values in the formula:



Thus,
The equation
is parallel to the line through the points 
Therefore,
the result for Part D) is
------> 
Case E) Point 
Determine the slope of JK
Insert the values into the formula:



Thus,
Any linear equation characterized by slope
will be parallel to the line that runs through the points 
Case F) Point 
Find the slope of LM
Substitute the values in the formula:



Thus,
The equation
is parallel to the line connecting the points 
Therefore,
the result for Part F) is
------> 