What multiplys to negative 36 but adds to 20

I'm not taking you through the method of solution.

You can do it with two numbers:  21.6619  and  -1.6619  (both rounded) .

The major difference is that a histogram is only used to plot the frequency of score occurrences in a continuous data set that has been divided into classes, called bins.  bar charts, on the other hand, can be used for a great deal of other types ofvariables  including  ordinal  andnominal  data sets.