I'm not sure if this is the answer but what the heck.
Mark (40,0) and (8,0) AS SO Mark where the 2 circles are | 40| __________________________O <== Mark here
35 / |
30 / |
25 / |
20 / |
15 / |
10 / |
5 / and mark where the zero is |
O 1 2 3 4 5 6 7 |8| 9 10 11