Polygons in the Coordinate Plane - Free Educational videos for Students in K-12

Polygons in the Coordinate Plane - By Anywhere Math

Transcript


00:0-1	Welcome anywhere . Math . I'm Jeff Jacobson . And
00:02	today we're gonna talk about polygons in the coordinate plain
00:06	, specifically how to plot them , how to draw
00:10	them in the coordinate plain . And then also how
00:12	to find things like perimeter and area . Once they're
00:15	in a coordinate plane , let's get started . Okay
00:36	before we get started with example one , you're probably
00:38	gonna want some graph paper or grid paper . If
00:42	all you have is lined paper , it can work
00:44	. You just have to make sure you're really really
00:46	organized and have nice straight lines . But if you
00:49	have a graph paper like this it's going to make
00:52	it a lot easier . So the first thing you're
00:54	gonna want to do obviously is to make your coordinate
00:58	plane . All we're using right now is the first
01:00	quadrant you can see I've got all the way up
01:03	from zero up to 15 on my x axis and
01:07	from zero up to 15 on my y . uh
01:09	but if you look uh nine is the greatest value
01:13	in my Y . And eight is the greatest in
01:17	my ex . So you could even just stop at
01:18	10 if you want . So go ahead first thing
01:21	draw your axes . And remember we only need the
01:25	first quadrant , everything is positive . So once you've
01:28	got that , let's read the example . So the
01:30	vertex is of a quadrilateral are a . Is that
01:34	24 Bs at 39 C . Is at 78 and
01:37	D . Is at 81 Draw the quadrilateral in this
01:41	coordinate plane . So the first thing , hopefully you
01:45	remember that the most important is the X . Value
01:50	. The X coordinate comes first , then the Y
01:53	. So when we're looking at these this too is
01:55	my X coordinate and that four is my Y coordinate
01:59	. So when I'm doing this I'm gonna be going
02:01	over to And then up four . Okay , so
02:05	a I'm going to plot that again , I said
02:08	over two . Right that's the X . Up for
02:11	that point is gonna go right there And then whenever
02:14	you plot points in a coordinate plane always labeled them
02:17	. So we're just going to call that a .
02:19	And that's at 24 . Next be is that 39
02:23	again ? Three is the X . Coordinate . So
02:25	on my X . Axis on going over three then
02:29	all the way up to nine . And that is
02:32	where that point is going again , label it be
02:35	is at 39 C . Is that seven ? Go
02:39	over seven up eight right there label that . And
02:45	then finally D over eight and up one Over eight
02:50	and up one . Okay . Uh And then label
02:53	that really it's it's pretty simple . You just got
02:57	to make sure that you always remember the X coordinate
02:59	comes first , then the Y . Um And if
03:02	you want to think about it , X comes first
03:05	in the alphabet , then why ? Maybe that could
03:07	help you out to remember it ? So we're almost
03:10	done . We've plotted our vertex is now I need
03:14	to draw the quadrilateral and this is pretty simple .
03:17	All you're doing is connecting the dots , but you
03:19	have to do it in order . I'm not going
03:21	A to C . And C . To be ,
03:23	I'm going A to B . Right ? So I
03:27	draw that then B . Two , C . Then
03:29	C . D . And then finally D . Back
03:31	to A . And there is my quadrilateral four sides
03:35	. It's close figure . And we're done . Here's
03:38	some to try on your own . Okay , here
03:47	we go with example to uh so same thing ,
03:50	first thing you're gonna want to do is create your
03:52	coordinate plane . Again , we're only using the first
03:54	quadrant . Uh and you don't have to go all
03:57	way up to 15 . If you look at the
03:58	numbers , I think you go to 10 . For
04:02	each , the X . and Y . Axis ,
04:03	that would be plenty . Um So let's see the
04:07	verses of a rectangle . R . F . Is
04:09	at 16 Gs at 76 H . Is at 72
04:13	And jay's at one to draw the rectangle in the
04:16	coordinate plain and then find its perimeter . So first
04:20	thing let's draw it . So we're going to plot
04:22	our points again . First one F . Is at
04:25	16 over one up six . It's gonna be right
04:29	there label it just like always next Gs at 76
04:35	Go seven over on my X . X . is
04:37	up six . I'm gonna be right there label that
04:41	G . Is at 76 Then H . Seven to
04:44	over seven up to write their label . And finally
04:49	J . Is at one to over one up to
04:53	right there label it . Now we've got our points
04:57	, they're all plotted , Remember after that we have
04:59	to draw uh So you're just connecting the dots .
05:02	F . To G . To H . H .
05:04	Two J . And J . Two F . And
05:06	it's gonna make a rectangle . Okay . So we're
05:10	halfway done . We have our our rectangle drawn ,
05:15	everything plotted , but now we've got to find our
05:18	perimeter . Uh And if you remember perimeter is just
05:21	the distance around the figure . Okay imagine if you
05:24	were walking all the way around it , how far
05:27	would you walk ? That's the perimeter . Uh There's
05:30	a couple ways to do it . One formula that
05:32	we're going to use is you have two lengths right
05:36	? For a rectangle , you've got two lengths .
05:38	This and this are are congruent . They're identical .
05:41	And you have to wits this with and this with
05:44	our also congruent . So let's find out what those
05:48	lengths and widths are . Well , we'll start with
05:51	the length here if you see Uh both for J&F
05:58	. They both have an X . coordinate of one
06:01	. Okay they're both over one but the y coordinate
06:05	is different . This one is only up to ,
06:07	this one's up six . So if you want to
06:09	know the length , we just find the difference of
06:12	those Y coordinates . So six minus two is four
06:16	. That's going to be my length . Okay I'm
06:19	going to substitute that in for L . Now .
06:22	How about the width ? Well we can look here
06:25	from J . two H . Uh notice here that
06:30	the X coordinates are not the same but the why
06:32	coordinates are they are both up to . Um So
06:36	I'm not going to be subtracting the y corn ,
06:38	it's like I did for my length Instead , I'm
06:41	subtracting my uh Excoriates , I'm finding the difference of
06:45	seven and 1 . Uh Which means this width is
06:50	six . And also if it's something this simple ,
06:53	you could also just count the squares , right ?
06:55	Each one of these is just one , so you
06:57	can even count right ? 123456 which is what we
07:02	just said . So I'm gonna substitute those in .
07:04	Uh l is going to be four and my width
07:09	is six . Make sure you use parentheses or else
07:11	it's gonna look like 24 but we want two times
07:14	four plus two times six . There's to each of
07:17	those simplify , you get eight plus 12 which finally
07:20	gives you 20 and there's no centimeters and meters .
07:24	These are just units . Uh And it's not units
07:27	squared because its perimeter it's just a distance . So
07:31	20 units is your answer . And here's one more
07:34	to try on your own . As always . Thank
07:41	you so much for watching and if you like this
07:43	video , please subscribe . Mhm .

Summarizer

DESCRIPTION:

OVERVIEW:

Polygons in the Coordinate Plane is a free educational video by Anywhere Math.

This page not only allows students and teachers view Polygons in the Coordinate Plane videos but also find engaging Sample Questions, Apps, Pins, Worksheets, Books related to the following topics.