You can put this solution on YOUR website!
Assuming you are not allowed to use a graphing calc or some other tool, you can always do it the old fashioned way.
Make a table with two columns. Label one column x and the other column y.
Pick a value for x and put it the column on row 1. Then square that value and write it's negative in the y column. Pick several other vaues for x and do that same thing.
Now plot those points (x,y) and then draw in the curve that connects them.
When you are done, go to this URL and use it to check your answer.