So I am thinking about Open Middle problems, transformations and parallel lines. As an 8th grader, is there more than 3 ways to “prove” two line segments are parallel?

**Method 1: Slope**

Slope of line a = 2/5, slope of line b = 2/5. Since the slopes are equal, they are parallel.

**Method 2: Line of Reflection**

Find a line *l *so that when you fold on that line, line *a *and line *b *match up perfectly.

**Method 3: Translation
**

Find a Translation where every point from line *a* will map to its corresponding point on line *b->* (X+4, Y-2).

(Method 2 and 3 may not be as formally worded here, just trying to anticipate possible student answers)

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