Assuming you are the person who posted the question on the link you provided, it appears you have already figured out the problem and that all you need at this point is the chart.
The chart would look like this
The stuff in the "total" row is extra to show how the columns add up straight down to get the two equations x+y = 6000 and 0.05x+0.09y = 400
Let me know if you have any questions. Thank you.
Note: for both accounts, t = 1 because 1 full year goes by to compute the annual simple interest.
Another side note: I agree with the answers x = 3500 and y = 2500, but the percentages have been swapped. It should be x = 3500 at 5% and y = 2500 at 9%.
Update: I'm just realizing that you said you needed the graph as well. It is shown below. I used GeoGebra to create the graph. The two lines intersect at (3500,2500) which represents the solution of this system.
