0:00:00.427,0:00:06.537 This video is aneat Pereemeter n Aurie, 0:00:07.867,0:00:11.183 Ah'l dae Pereemeter oan the cair[br]n Aurie oan the richt. 0:00:11.183,0:00:16.443 Ye'r proablie fameeliair wi the idea,[br]bit we'l revisit it in case ye'r no. 0:00:16.443,0:00:20.533 Pereemeter is the distance[br]tae gae around somit, 0:00:20.533,0:00:24.093 Gif ye were tae pit ae fence aroond[br]or measure somit. 0:00:24.093,0:00:27.750 Gif ye wer tae pit ae tape roond ae figure[br]hou lang that tape wid be. 0:00:27.750,0:00:35.447 Sae, gif Ah hae ae rectangle,[br]n ae rectangle is ae figure 0:00:35.447,0:00:40.140 that haes fower n fower richt angles. 0:00:40.140,0:00:46.537 This is ae rectangle here,[br]Ah hae, 1, 2, 3, 4 richt angles n 4 sides, 0:00:46.537,0:00:53.537 n the opposite sides ar equal in langth. 0:00:53.537,0:01:00.923 Mibbe Ah'l lable the points,[br]A, B, C, n D, 0:01:00.923,0:01:02.873 n lat's say that we ken the folaein, 0:01:02.873,0:01:06.947 we ken that AB = 7, 0:01:06.947,0:01:12.673 n we ken that BC is equal tae 5. 0:01:12.673,0:01:17.443 We want tae ken whit[br]the pereemeter o ABCD is. 0:01:17.443,0:01:26.363 The pereemeter o rectangle ABCD[br]is equal tae 0:01:26.363,0:01:28.070 the sum o the langth o the sides. 0:01:28.070,0:01:30.228 Gif Ah wis tae big ae fence 0:01:32.438,0:01:35.281 Ah'd hae tae mesure hou lang this side is, 0:01:35.281,0:01:36.800 we awreadie ken that that's 7, 0:01:38.650,0:01:45.612 That side ower thaur is 7 units lang,[br]7 plus, this langth wil be 5, 0:01:45.612,0:01:51.200 Thay tell us that BC is 5,[br]DC is gaun tae be 0:01:51.200,0:01:53.963 the same langth aes AB,[br]n that's 7 again. 0:01:55.663,0:02:00.555 Sae DA or AD whitiver ye want tae caa it,[br]wid be the same langth aes BC, 0:02:00.555,0:02:03.721 n that's 5 again,[br]sae plus 5 again. 0:02:03.721,0:02:07.543 Sae ye hae 7 plus 5 is 12,[br]plus 7 plus 5 is 12 again, 0:02:07.543,0:02:13.502 sae ye'r gaun tae hae ae pereemeter o 24. 0:02:14.012,0:02:19.489 Ye coud gae the ither road,[br]lat's say that ye hae ae square 0:02:19.489,0:02:25.250 This is ae byordinair case o ae rectangle,[br]ae square haes 4 sides 0:02:25.250,0:02:29.112 n 4 richt angles n aw o the sides ar equal 0:02:29.112,0:02:36.885 Sae lat me draw ae square here,[br]ma best attempt. 0:02:36.885,0:02:46.473 Sae this is A, B, C, D, n we'r[br]gaun tae say that this is ae square, 0:02:46.473,0:02:57.171 n lat's say that this square[br]haes ae pereemeter o 36. 0:02:57.171,0:03:01.787 Sae, whits the langth o the 4 sides,[br]weel aw o the sides hae the same langth, 0:03:01.787,0:03:09.587 Lat's caa thaim x, sae gif AB is x,[br]than BC is x, than DC is x, n AD is x. 0:03:09.587,0:03:13.472 Aw o thir sides ar congruent,[br]thay aw hae the same langth, 0:03:13.472,0:03:16.570 We caa that x, sae gif we want[br]tae fynd oot the pereemeter 0:03:16.570,0:03:28.696 it'l be x + x + x + x, or 4x,[br]n that equals 36, 0:03:28.696,0:03:32.812 thay gave us that in the proablem,[br]n tae solve this 4 * sommit is 36, 0:03:32.812,0:03:34.905 ye coud solve that in ye'r heid, 0:03:34.905,0:03:42.338 bit we coud deevide baith sides bi 4,[br]n ye get x = 9, 0:03:42.338,0:03:47.047 sae this is ae 9 bi 9 square,[br]this width is 9, 0:03:47.047,0:03:50.787 this is 9, n the heicht here[br]is 9 n aw. 0:03:50.787,0:03:52.927 Sae that's pereemeter, 0:03:52.927,0:03:58.284 Aurie is ae mesure o hou muckle space[br]dis this tak up in twa dimentions. 0:03:58.284,0:04:05.084 N yin waa tae think oan aurie is[br]gif Ah hae 1 bi 1 square, 0:04:05.084,0:04:07.993 N whan Ah say 1 bi 1[br]it means that ye yinlie hae tae speceefie 0:04:07.993,0:04:11.702 2 dimentions fer ae square or rectangle,[br]cause the ither 2 ar gaun tae be the sam. 0:04:11.702,0:04:14.851 Fer exaumple, ye coud caa this[br]ae 5 bi 7 rectangle, 0:04:14.851,0:04:18.326 Cause richt awaa that says that[br]this side is 5 n that side is 5, 0:04:18.326,0:04:20.523 this side is 7 n that side is 7, 0:04:20.523,0:04:22.856 N fer ae square ye coud say[br]it's ae 1 bi 1 square 0:04:22.856,0:04:26.310 Cause that speceefies aw o the sides,[br]ye coud realie say fer ae square 0:04:26.310,0:04:34.243 where 1 side is 1 than aw sides ar 1,[br]sae this is ae 1 bi 1 square. 0:04:34.243,0:04:37.038 Ye can see the aurie o onie figure aes 0:04:37.038,0:04:41.502 hou monie 1 bi 1 squares[br]can ye fit oan that figure? 0:04:41.502,0:04:45.594 Sae, fer exaumple, gif we were[br]gaun back tae this rectangle here, 0:04:45.594,0:04:48.634 n Ah wantit tae fynd oot[br]the aurie o this rectangle, 0:04:48.634,0:04:52.715 n the notation that we can uise fer aurie[br]is tae pit sommit in brackets, 0:04:52.715,0:04:59.717 Sae the aurie o rectangle ABCD,[br]A, B, C, D, 0:04:59.717,0:05:04.262 is equal tae the nummer o 1 bi 1 squares[br]that we can fit oan this rectangle 0:05:04.262,0:05:07.440 Lats ettle tae dae that bi haund,[br]Ah think... [Bletherin], 0:05:09.420,0:05:14.337 Lats pit nummer o 1 bi 1s, lat's see,[br]we hae 5 1 bi 1 Squares this waa, 0:05:14.337,0:05:17.366 n 7 this waa, sae Ah'm gaun tae[br]dae ma best tae draw it tydie, 0:05:17.366,0:05:26.444 Sae that's 1, 2, 3, 4, 5, 6,[br]n than 7, 0:05:26.444,0:05:29.263 1, 2, 3, 4, 5, 6, 7, 0:05:29.263,0:05:37.211 Sae gaun alang 1 o the sides lik this,[br]ye coud pit 7 alang 1 side. 0:05:37.211,0:05:44.144 N than ower here hou monie can we,[br]lat's see, that's 1 raw, that's twa raws, 0:05:44.144,0:05:50.802 N we hae three raws, n than 4 raws,[br]n than 5 raws, 1, 2, 3, 4, 5, 0:05:50.802,0:05:54.592 N that maks sence,[br]caus this is 1, 1, 1, 1, 1, 0:05:54.603,0:05:58.853 Shid eik up tae 5,[br]thir's 1, 1, 1, 1, 1, 1, 1, 0:05:58.863,0:06:01.466 Shid eik up tae 7,[br]Ay, thaur's 7. 0:06:01.466,0:06:05.153 Sae this is 5 bi 7,[br]n ye cou d coont thir, 0:06:05.153,0:06:08.260 n this is strechtfowerd multipleecation,[br]gif ye wantit tae ken 0:06:08.260,0:06:10.147 the hale nummer o cubes,[br]ye coud coont thaim, 0:06:10.147,0:06:13.036 or ye coud say, Ah hae 5 raws,[br]7 coloumns, 0:06:13.036,0:06:16.668 Ah'm gaun tae hae 35 -- did Ah say cubes?,[br]squares -- 0:06:16.668,0:06:19.590 Ah hae 5 squares in this direction,[br]n 7 in this direction, 0:06:19.590,0:06:22.025 Sae Ah'm gaun tae hae 35 squares aw up, 0:06:22.025,0:06:27.035 Sae the aurie o this figure is 35, 0:06:27.037,0:06:30.746 N sae the general methid, ye coud say,[br]Ah'm gaun tae tak 1 dimention 0:06:30.746,0:06:32.750 n multiplie it bi the ither dimention 0:06:32.750,0:06:44.081 Sae gif Ah hae ae rectangle,[br]lat's say the raectangle is 1/2 bi 2, 0:06:44.081,0:06:46.926 Thae ar it dimentions,[br]ye can juist multiplie, 0:06:46.926,0:06:50.232 1/2 * 2, the aurie is gaun tae be 1. 0:06:50.232,0:06:52.720 Ye micht say, 'Whit dis 1/2 mean?', 0:06:52.720,0:06:59.261 In this dimention it means that[br]Ah can yinlie fit 1/2 o ae 1 bi 1 square, 0:06:59.261,0:07:02.485 Sae gif Ah want tae dae ae hale[br]1 bi 1 square, it's ae wee bit distortit, 0:07:02.485,0:07:03.483 it wid lui lik that. 0:07:03.483,0:07:07.577 Sae Ah'm yinlie daein 1/2 o 1,[br]Ah'm daein anither 1/2 o 1 juist lik that, 0:07:07.577,0:07:12.957 n sae whan ye eik this n this thegeather,[br]ye'r gaun tae get ae hale 1, 0:07:12.957,0:07:15.584 Nou, aneat the aurie o ae square,[br] 0:07:15.584,0:07:19.793 weel ae square's juist ae byordinair case[br]whaur the width n the langth ar the sam. 0:07:19.793,0:07:24.353 Sae gif Ah hae ae square,[br]lat me draw ae square here. 0:07:25.480,0:07:31.580 Lat's caa that x, y, z, lat's mak it s. 0:07:31.580,0:07:34.100 Lat's say that Ah wantit[br]tae fynd the aurie, 0:07:34.100,0:07:37.583 n lat's say that yin side here is 2,[br]sae XS is equal tae twa, 0:07:37.583,0:07:41.516 n Ah want tae fynd the aurie o [XYZS],[br] 0:07:41.516,0:07:45.632 sae yince mair Ah uised the brackets[br]tae speceefie the aurie o this figure 0:07:45.632,0:07:48.834 o this poliegon here, this square,[br]n we ken that it's ae square. 0:07:48.834,0:07:50.561 We ken that aw o the sides ar equal. 0:07:50.561,0:07:52.934 Weel, it's ae byordinair case[br]o ae rectangle, 0:07:52.934,0:07:56.345 we multiplie the langth bi the width,[br]we ken that thay'r the same thing, 0:07:56.345,0:08:00.660 Gif this is 2, than this is 2,[br]sae ye juist multiplie 2 bi 2, 0:08:00.660,0:08:02.788 Or, gif ye want tae think o it[br]ye square it, 0:08:02.788,0:08:04.887 That's whaur the word comes fae,[br]squarein sommit. 0:08:04.887,0:08:09.787 Sae ye multiplie 2*2,[br]that's equal tae 2 squared, 0:08:09.787,0:08:12.835 That's where the word comes fae,[br]fyndin the aurie o ae square. 0:08:12.835,0:08:16.105 That's equal tae 4. 0:08:16.105,0:08:23.635 N ye can see that ye can easielie fit[br]4 1 bi 1 squares oan this 2 bi 2 square.