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## Congruence and similarity

Current time:0:00Total duration:1:13

# Non-congruent shapes & transformations

CCSS Math: 8.G.A.2, HSG.CO.B.6

## Video transcript

So we have another
situation where we want to see whether these
two figures are congruent. And the way we're
going to test that is by trying to transform
this figure by translating it, rotating it, and reflecting it. So the first thing that
might-- let me translate it. So if these two things are
congruent, looks like point E and the point that I'm
touching right now, those would correspond
to each other. Let me try to rotate
it a little bit. So let me rotate-- whoops, I
don't want to rotate there, I want to rotate around
point E since I already have those on top of each other. So just like that. And it looks like now, if I
reflect it across that line, I'm going to be-- oh
no, I'm not there. You see, this is tricky. See, when I reflect it, this
point, this point, this point, and this point seem to be
in the exact same place, but point C does not
correspond with that point right over there. So these two polygons
are not congruent. And this is why it's
important to do this, to make sure the
rotations work out. So these two are not congruent. I'm not able to get them to
exactly overlap each other just through translations,
rotations, and reflections. So are these polygons congruent? No.