How many solutions does this system of equations have?

a. exactly two
b. none
c. exactly one
d. infinitely many

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.