1
00:00:01,070 --> 00:00:09,570
quadrilaterals exercise number one square given its side first thing we are

2
00:00:09,570 --> 00:00:23,140
going to place the square or the bubble to place the right angles on B and on a

3
00:00:23,140 --> 00:00:34,179
we need this to be really accurate we have both right angles and now with the

4
00:00:34,179 --> 00:00:49,969
compass we transport AB up. So from B we draw this arc and with the same measurement you

5
00:00:49,969 --> 00:00:59,750
then change AB. With the same measurement you go up two. Doing that you get two equal

6
00:00:59,750 --> 00:01:20,250
sides now you got C and D and close the shape CD so you have a square that is a

7
00:01:20,250 --> 00:01:31,219
square number two rectangle given the two sides good so we are going to start

8
00:01:31,219 --> 00:01:47,810
we are going to use this line and a square so we draw our right angle our

9
00:01:47,810 --> 00:01:54,709
right angle and here we are going to use one of the sides the bigger one so it's

10
00:01:54,709 --> 00:02:07,810
going to be 70 so from the beginning of the line till the end you get the side

11
00:02:07,810 --> 00:02:20,090
for example a B this is again 70 okay now you're going to use the right angle

12
00:02:20,090 --> 00:02:41,960
right angle on B right angle on a and from a and B up we are going to measure

13
00:02:41,960 --> 00:02:53,580
45. So here we measure 45. This is almost, yes, it's accurate. And here I need a little

14
00:02:53,580 --> 00:03:05,520
bit more. I need to extend this line up a little bit. So you have 45. You get the two

15
00:03:05,520 --> 00:03:08,479
points, remember that the points are

16
00:03:08,479 --> 00:03:12,840
small circles with a little

17
00:03:12,840 --> 00:03:17,419
void inside, blank, connect

18
00:03:17,419 --> 00:03:21,400
the two points, that's it, and you

19
00:03:21,400 --> 00:03:27,110
get C and D, that is the

20
00:03:27,110 --> 00:03:31,229
rectangle. Number three, rectangle

21
00:03:31,229 --> 00:03:34,789
given one side, and the diagonal AC

22
00:03:34,789 --> 00:03:49,710
So, we are given the diagonal, this is AC, because this would be a side, would be AB or AD, so AC is the diagonal, okay?

23
00:03:49,770 --> 00:03:51,650
We have to read carefully.

24
00:03:53,030 --> 00:03:59,669
Considering this is the diagonal, we are going to place the center of the rectangle.

25
00:04:02,620 --> 00:04:08,840
So, in order to get the center, you need to do, again, a segment by sector.

26
00:04:09,800 --> 00:04:16,699
So, we place a compass on A, and with any radius bigger than the middle,

27
00:04:17,699 --> 00:04:31,519
so we draw an arc up and down, and with the same distance, you change the center and see up and down.

28
00:04:31,680 --> 00:04:35,839
so the four radius are the same

29
00:04:35,839 --> 00:04:42,839
once you have that we are going to draw the segment by sector but

30
00:04:42,980 --> 00:04:46,639
in this case we only need the center so we're going to simplify

31
00:04:46,639 --> 00:04:53,120
doing this, doing these three lines

32
00:04:53,120 --> 00:04:56,399
because what we really need

33
00:04:56,399 --> 00:05:00,560
is this center O, these points

34
00:05:00,560 --> 00:05:08,819
My advice is that you place them properly, name them as 1 and 2, for example.

35
00:05:10,079 --> 00:05:22,600
Good. Once we have O, we are going to draw a circle, a circumference, center O, and passing through A and B.

36
00:05:24,360 --> 00:05:29,360
So, we are going to draw this O.

37
00:05:32,029 --> 00:05:34,149
Okay, I made a mistake, so I have to repeat.

38
00:05:34,149 --> 00:05:44,449
So, center O, and we draw the circle passing through A and B.

39
00:05:49,839 --> 00:05:50,040
Okay?

40
00:05:50,879 --> 00:06:06,860
And once you have the circle, the rectangle is going to be inscribed inside this circumference.

41
00:06:06,860 --> 00:06:21,699
So now we have to use the data of the side and we can place either on A or C this side.

42
00:06:21,699 --> 00:06:38,360
So, for example, we can use C. We can draw here from C one line, and here we are going to mark exactly 42.

43
00:06:38,360 --> 00:07:02,240
42 this is 42 okay good so we are going to name this as L 42 good good so now once you have that

44
00:07:02,240 --> 00:07:27,269
We take this measurement from C and transport 42 up till it crosses, okay?

45
00:07:27,689 --> 00:07:35,629
So you place a compass here on C and you transport this distance on the circumference.

46
00:07:35,629 --> 00:07:45,290
And you, without changing the measurement, you place the compass on A and do the same up.

47
00:07:48,250 --> 00:07:58,389
Okay, so you will get one point 42 from C and another point 42 from A.

48
00:07:58,389 --> 00:08:06,829
If you connect these points, this will be B and this will be V.

49
00:08:08,029 --> 00:08:20,329
capital letter so if you're going to get the four points you will get the rectangle

50
00:08:22,670 --> 00:08:37,289
which have we has which has a ac as a diagonal number four rhombus given its side

51
00:08:37,289 --> 00:08:53,590
48 this is really easy because the four sides in a rhombus are the same so if you just draw

52
00:08:53,590 --> 00:09:07,639
from for example front a in any red direction we draw a line for example there that measure

53
00:09:07,639 --> 00:09:27,610
exactly 48. So this is 48. This is their side. And now with the compass we are going to draw

54
00:09:27,610 --> 00:09:44,580
one arc from A 48 and from C 48. You will see that they cross each other because this is like

55
00:09:44,580 --> 00:09:57,480
a segment by sector you will get B sorry and G and if you connect the four

56
00:09:57,480 --> 00:10:18,309
points you get the rhombus from a to B and G and from B C DC that is the rhombus

57
00:10:18,309 --> 00:10:32,830
the four sides 48 relax last exercise the rhomboid given to sites okay because

58
00:10:32,830 --> 00:10:42,429
a B is given okay and they are giving us the other side the other side is 35 okay

59
00:10:42,429 --> 00:10:52,070
Good. If we review this scheme here, the rhomboid is this one, okay?

60
00:10:52,870 --> 00:11:01,309
It's like a rectangle, but with angles that are not right angles.

61
00:11:01,610 --> 00:11:04,509
So we have acute and obtuse angles.

62
00:11:04,730 --> 00:11:08,970
These two are obtuse, these two are acute.

63
00:11:08,970 --> 00:11:20,309
so considering we are given 30 okay we are going to place 30 degrees good you can use your bevel

64
00:11:20,309 --> 00:11:32,340
because your bevel has 30 degrees in the smaller angle but i'm going to use this tool to place

65
00:11:32,340 --> 00:11:56,259
I'm placing this on zero, okay, and this is 30 degrees. So if I connect A with this point, we will get here an angle. I'm going to name that angle.

66
00:11:56,259 --> 00:12:19,519
So with the compass, we are going to draw a small circle here, a small arc, like this. And this is going to be 30 degrees. That is the angle on A.

67
00:12:19,519 --> 00:12:30,149
Good. I just wanted to show you that you can also use the bevel, okay? This ruler. This

68
00:12:30,149 --> 00:12:43,090
ruler has 30, 60, 90. So you can use the ruler like this. You can place it with a smaller

69
00:12:43,090 --> 00:12:47,110
angle, and even if the tip doesn't

70
00:12:47,110 --> 00:12:49,750
work, you can place another ruler here

71
00:12:49,750 --> 00:12:55,129
to connect with A. So you take this out

72
00:12:55,129 --> 00:12:58,110
and draw the line. So you will get the same angle.

73
00:12:58,950 --> 00:13:02,889
Once we have 30, we know

74
00:13:02,889 --> 00:13:06,809
that the other side is 35. So you can take

75
00:13:06,809 --> 00:13:10,450
the ruler and measure here the

76
00:13:10,450 --> 00:13:32,750
35, 35. Great. So this is going to be D. And knowing that this is a parallelogram, so we need the sides to be parallel, you can close the shape using parallels.

77
00:13:32,750 --> 00:13:51,690
So, we can place the ruler on this side, AD, place the other one here, and, oh, I'm going to repeat, sorry, because if it moves, you have to repeat.

78
00:13:52,690 --> 00:13:58,850
So, again, we place the compass, sorry, the ruler is like this, okay?

79
00:13:58,850 --> 00:14:11,840
The straight one stands still, the other one moves till you reach B and draw the parallel side, something like this.

80
00:14:11,840 --> 00:14:28,049
And you have to do the same with the baseline, so you place the ruler here on AB, sorry, here, so the first ruler goes here on AB,

81
00:14:28,049 --> 00:14:38,970
the other one goes there you go up passing through D and this way you get

82
00:14:38,970 --> 00:14:51,450
a perfect rhomboid this is C you will get another 35 here and another side

83
00:14:51,450 --> 00:14:57,870
like AV but on top and all the lines are parallel