About this video
Two line segments are congruent when they have exactly the same length. The video checks three pairs of segments on a number line, finding lengths by subtracting endpoints and comparing them.
You'll be able to
- explain what congruent line segments are.
- find segment lengths on a number line and decide if two segments are congruent.
Key words
- congruent segments
- Line segments that have exactly the same length.
- line segment
- Part of a line between two endpoints.
Transcript
Are line segment AB and line segment CD congruent? So let's look at these right over here. AB is this line segment right over here, and CD is this one right over here. AB has length of 1. It goes from 2 to 3. And CD has length of 1. It goes from 4 to 5. So they have the exact same length.
These are just line segments with the exact same length. So yes, they are congruent. Yes. Let's do a couple more. Are AB and CD congruent? And you can just eyeball this. AB is much longer than CD. AB is of length 4. It goes from negative 5 to negative 1. CD is only of length 1.
It goes from 1 to 2. So no, they are not congruent. They have different lengths. Let's do one more. Are AB and CD congruent? Let's see-- AB has length 2. It goes from negative 1 to 1. CD is of length 3. So they're not congruent. No.
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