Presenting the table vertically makes it easier to read:
X F(x)
-1 -5
0 -1
1 3
I see that if x increases by 1 from 0 to 1, y increases by 4 from -1 to 3. Thus, the slope of the line represented by the table is:
4
m = -------------- = 4/1 = 4
1
So, our two lines have the same slope: 4.
g(x) = 4x + 3; f(x) = 4x - 1
but they have different y-intercepts. Thus, the 2 lines are parallel and never cross one another.
