ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


Geometry Videos 51 videos

Transformations
15751 Views

If you were looking for the trailer for the new Michael Bay movie, you've got the wrong number. Transformations are rotations, reflections, and tra...

Translations and Functions
1284 Views

Translations: now without the trans fat. Functions: now without the…fun? Wait, scratch that. Now with extra fun! Don’t believe us? There's only...

CAHSEE Math 5.4 Measurement and Geometry
342 Views

Measurement and Geometry Drill 5 Problem 4. Which of the following best describes the transformation as shown in the graph below?

See All

Midsegment Theorem 4647 Views


Share It!


Description:

Who knew triangles had midsegments? We did.

Language:
English Language

Transcript

00:05

Midsegment Theorem, a la Shmoop.

00:08

Curious Jorge is competing in the annual ABC triangular jungle gym race for the first time.

00:14

The fastest monkey gets a lifetime supply of bananas.

00:18

Unfortunately, Jorge is the youngest monkey in the 13-18 age category,

00:23

so he can't rely on sheer speed to win.

00:25

He might be able to give himself a leg up if he can

00:28

figure out the length of each section of jungle gym...

00:33

AC is 16 feet, AB is 18 feet, and BC is 6 feet.

00:40

D is the midpoint of AC and E is the midpoint of AB.

00:45

What is the length of DE?

00:49

Well, to figure this out, we can use something called the midsegment theorem.

00:53

The midsegment theorem tells us that, in a triangle...

00:56

...the segment joining the midpoints

00:58

of any two sides will be parallel to the third side and half its length.

01:02

In this case, DE is a segment joining the midpoints of any two sides.

01:06

Therefore, by the midsegment theorem, DE is parallel to BC,

01:11

and is half its length, so we can write DE equals half BC.

01:16

Since BC is 6, we can substitute 6 into the formula, multiply it by ½,

01:23

and get the length of DE, which is 3 feet.

01:26

As it turns out, all of the older monkeys

01:28

exert themselves too much early on and are wiped out for the home stretch...

01:35

...while Jorge has paced himself perfectly, and winds up the top banana!

Related Videos

Surface Area of Cylinders
14741 Views

Haven't you always wondered how much cardboard it takes to encase a trunk warmer for your pet elephant?

Perimeter of Irregular Shapes
4864 Views

Want to figure out the area and perimeter of irregular shapes? Break them down into regular shapes. For example, a flower can be broken down into s...

Introduction to 3D Geometry
55503 Views

It's one thing when all those shapes are sitting flat on the page. But when they start popping out and invading our personal space bubble, we get a...

An Introduction to 3D Geometry
815 Views

Does thinking about 3D Geometry get you bent out of shape? Never fear! Watch this video and figure out some fun new shapes to bend back into. We're...

ACT Math 3.5 Plane Geometry
394 Views

ACT Math: Plane Geometry Drill 3, Problem 5. How long would it take for the wheel to make two rotations?