- Which two lines in the square grid below are parallel to each other?
In order for the lines to be parallel, the lines need to have the same gradient (or same ratio of base to height or vice versa)
Let us compare lines AD and HE
We can see from above that AD has a base of 8 squares compared to line HE which has a base of 7 squares. Although AD and HE do have the same height, lines AD and HE do not have an equal base. Therefore, lines AD and HE do not have the same gradient (or ratio) and they are not parallel.
Lines BG and CF have the same base of 3.5 squares and same height of 7 squares. Lines BG and CF have the same ratio of base and height. Therefore, lines BG and CF have the same gradient (or ratio) and they are parallel.
Line DE has a base of 1 square and height of 5 squares. Line DE does not have another line with a similar base and height ratio to compare with and have no comparable parallel line.
