Question

Which pair of slopes could represent parallel lines?

m = 7; m = 49
m = 2/7; m = 7/2
m = -3, m = -9/3
m = -1/2, m = -2

Answer 1

m = -3, m = -9/3

because when you divide -9/3, you get -3, so the slopes would be the same.
If the slopes are the same (and their intercepts are different) then that pair of slopes represents parallel lines!