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Squares and Rectangles Videos 6 videos

Perimeter of a Rectangle
3862 Views

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

SAT Math 7.3 Geometry and Measurement
183 Views

SAT Math 7.3 Geometry and Measurement

SAT Math 9.4 Geometry and Measurement
184 Views

SAT Math 9.4 Geometry and Measurement

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Perimeter of a Rectangle 3862 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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