rise over run* it means in a slope, for example -5/5, the nominator is the rise and the denominator is the run, so you would go down by 5, because the rise is negative, and go right by 5 because the run is positive.
One way ti find the common denominatir is to check ti see if ine denominator is a factor to the other deniminator if it is then the deniminator can be used as the common denominator when the two deniminators are the same compare the numerators
