Equation has a graph parallel to the graph of y=-2x-8

I'd transcribe the word problem directly into an inequality, as follows:

(1/2)n is greater than or equal to 10.  Mult. both sides by 2 results in

"n is greater than or equal to 20" (answer)

Draw a horiz. number line to represent n.  Place a solid dot at x = 20.  Draw an arrow from n=20 to the right.  That's it.