Since slope is calculated using the formula m = startfraction v 2 minus v 1 over x 2 minus x 1 endfraction, the slope of both lines is equivalent to ________. it is given that the lines are parallel, and we calculated that the slopes are the same. therefore, parallel lines have the same slopes. startfraction v minus z b over x minus z a endfraction startfraction w minus x a over v minus z b endfraction