A and D are correct. To understand this, you need to know that this scenario gives us a total (2 1/2 cups) and a part (1/4). When you have these 2 pieces of information you have either a division problem with a total divided into parts (choice D) or you have one part and a totol shown as a multiplication problem (choice A).
Parallel lines have the same slopes (but different y intercepts). Parallel lines never cross. Parallel lines are the same distance from each other no matter where you are on either line. Think of it like a pair of perfectly straight railroad tracks.
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Perpendicular lines cross at one point. The two lines form a 90 degree angle. The two slopes multiply to -1, which is another way of saying that the slopes are negative reciprocals of one another. For example, a line with a slope of 2/3 and another line with a slope of -3/2 has these two values multiply to -1; therefore showing they are perpendicular lines.
