Transversal.

This line here looks like a transversal a transversal!

That's a transversal.

of the transversal.

So if I just extended it like that, you see it's a transversal, and I could go the other direction as well.

Because, if you view this as a transversal, if you view DC as a transversal, then you see that's a transversal between these two lines.

You have a transversal, parallel lines

And now we have a transversal

Fancy word for something very simple, transversal.

Now whenever you have a transversal crossing parallel

So we have a transversal between parallel lines.

So, in the first time we view this as the transversal AC is a transversal of AB and CD which are parallel lines

lines, then this segment up here is a transversal.

This is a transversal, these two lines are parallel

And then we have these transversals that go across them, so you have this transversal BC right over here and we have transversal AD

And if you just think about it, or if you even play with toothpicks or something, and you keep changing the direction of this transversal line, you'll see that it actually

So, first of all we view this as a transversal

We view AC as a transversal of AB and CD

So it's a classic parallel line with a transversal problem.

So we have a transversal that intersects the two parallel lines.

So if that is a transversal, what do you know about transversals?

All a transversal is is another line that actually intersects those two lines.

But what I want to do is explore the angles of a transversal.

Now AB is a transversal and BD and AC are the parallel lines

And I will introduce you to a new complicated geometry term called a transversal.

So this line right over here this is transversal so we know for example

In the accompanying diagram, parallel lines L and M are cut by transversal T.

And so if you look at this angle up here on this top line where the transversal intersects the top line, what is the corresponding angle to where the transversal intersects this bottom line?

They kind of play the same role where the transversal intersects each of the lines.

What do we know about corresponding angles for parallel lines when you have a transversal?

These are parallel, that's a transversal, this is a corresponding angle of that, so they're congruent.

This is alternate interior angles are congruent when you have a transversal intersecting two parallel lines

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And so if you have a transversal, the corresponding angles are congruent, you're dealing with parallel lines.

That's a parallel line, that's a parallel line, so this is a transversal between two parallel lines.

There's actually several ways that we can do this problem but we know that this is transversal

And I drew it more so if you say that this line right here is a transversal.

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Direction

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Direction?

So, we know that AB is parallel to CD by alternate interior angles of transversal intersecting parallel lines

Of One Direction! ...It is Liam of One Direction.