An ordered pair (x,y) is an x value, and an associated y-value (so that f(x) = y).

You can find as many as you need for a continuous function if you know the function f(x). So for the two functions you have, rearrange them to give y as a function of x. Both rearrange to:

y = 1/2x - 6

In other words, both represent the same straight line. So just pick a value of x, and substitute it in. For example, x=0:

y = 1/2(0) - 6

y = -6

This gives (0, -6) as an ordered pair. Or, substitute in x=12 instead:

y = 1/2(12)-6

y = 0

That would give (12,0). You can find as many points on the line as you like by substituting in values of x and finding the associated value of y.