Answer :

-37 = n
      23

to solve for n, undo what is happening to the n. if the n is being divided by 23 to get -37, then multiply both sides by 23 to figure out what n is. 

-37 * 23 = n * 23 
                  23

-851 = n
the 23 is crowding the n by division
so to undo that we multiply both sides by 23
to get n alone

n = -37 * 23 = - 851

so n = - 851