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Perimeter of a Rectangle 3861 Views


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Description:

Rectangles just love to have perimeters. And we just love to measure them.

Language:
English Language

Transcript

00:04

Perimeter of a Rectangle, a la Shmoop. Lance Armstrong has had a media storm of evil-wishers

00:11

show up at his doorstep recently.

00:14

He needs to install a state-of-the art video-surveillance Wi-Fi-controlled weapon-of-mass-destruction-armed

00:20

electric fence.

00:23

But he donated nearly all his money to cancer research.

00:26

So he’s going to have to buy a fence on the cheap…

00:30

… which means he needs to know how to build a rectangular fence around his compound with

00:34

the smallest perimeter. Lance knows that he needs at least 36 square

00:38

miles of land for his palatial mansion, biking trails, and factory of lies.

00:46

What is the smallest possible perimeter for his rectangle?

00:54

The formula for the area of a rectangle is length times width…

00:58

…while the formula for the perimeter is the sum of 2 times the length and 2 times

01:07

the width. Or the sum of all four sides.

01:12

To get an area of 36, here our options for the rectangle’s dimensions:

01:21

36 by 1 18 by 2

01:23

12 by 3 9 by 4

01:26

and 6 by 6.

01:28

And here are their corresponding perimeters: 70, 40, 30, 26, and 24.

02:02

Of these choices, 24 is the smallest perimeter possible.

02:09

And good thing it’s one of our answer choices!

02:14

Hello, answer (B).

02:23

Lies, Lance, lies.

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