y = 3x + 7....slope is 3, y int is 7
y = 3x + 2...slope is 3, y int is 2
when the slopes are the same, but the y intercepts different, then it is a parallel line with no solutions.
little tip :
slopes same, y int different, = no solution
slopes same, y int same = infinite solutions
slopes different, y int different = 1 solution