Question

There is no war in Ba Sing Se.

Answer 1

Prove that segment DE is parallel to segment AB.

Answer 2

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Answer 3

Since they give you the coordinates, I wonder if it's as simple as just finding the slopes of both of them. Lines with equal slopes are parallel, after all.

Well, unless they're actually the same line. But you can prove that's not the case because they are horizontal lines (provable once you've shown their slopes are 0) and their y values are different.

Answer 4

So I just find their slope? Should I use: y2 - y1/x2 - x1

Answer 5

Yes.

I should point out there may be some fancy trick using the fact that it's a triangle that you're expected to use that I'm neglecting.

Answer 6

I'm pretty sure it's just fine to find their slope, so I'll do that.

Answer 7

Thank you =3

Answer 8

To be really rigid about it, you should say that if you extend them into lines, the lines would be parallel. Then I think, by definition, any segments of those lines would be parallel also.

Answer 9

Glad that helped. :D