1 00:00:04,910 --> 00:00:10,810 We are going to draw the worksheet Lacus, okay? 2 00:00:11,750 --> 00:00:13,750 So exercise number one 3 00:00:14,210 --> 00:00:23,410 We are going to place 4 00:00:25,390 --> 00:00:26,989 The 5 00:00:26,989 --> 00:00:32,729 Points that keep the same distance from A and B in order to do that 6 00:00:33,530 --> 00:00:35,329 with a compass 7 00:00:35,329 --> 00:00:37,070 We will draw 8 00:00:37,070 --> 00:00:38,869 an arc 9 00:00:38,869 --> 00:00:41,549 from B with any radius 10 00:00:42,109 --> 00:01:01,920 So you draw top and bottom with any radius and with the same radius, so no changing the radius here in the compass, we mark top and bottom again. 11 00:01:01,920 --> 00:01:12,480 okay so you have two a couple of arches that cross each other this we are going to name 12 00:01:13,519 --> 00:01:32,099 these dots as one and two okay place the ruler carefully and connect one and two 13 00:01:32,099 --> 00:01:44,840 and draw the segment this way we are going to get the division of the segment in two we are 14 00:01:44,840 --> 00:01:56,780 going to get the midpoint M and the perpendicular this symbol means perpendicular on M on the 15 00:01:56,780 --> 00:02:22,409 segment. This construction is called segment bisector. Exercise number two is draw the 16 00:02:22,409 --> 00:02:31,610 locus of all points at 25 millimeters from point P. So we are going to draw points or 17 00:02:31,610 --> 00:02:40,509 place points that keep that distance 25 from P. We are going to measure this distance 18 00:02:40,509 --> 00:03:07,000 on a straight line in any direction, we measure with accuracy from P25. We are going to, we 19 00:03:07,000 --> 00:03:22,949 erase the rest of the line, so we keep the 25 millimeters. This is the mark for 25. Draw 20 00:03:22,949 --> 00:03:40,259 an arrowhead clean this arrowhead must be neat clean and an isosceles triangle 21 00:03:40,259 --> 00:03:54,030 and on top of the line we are going to write just in the middle r25 now with 22 00:03:54,030 --> 00:04:08,039 compass we can draw the locus, the geometrical locus, of all dots there, all 23 00:04:08,039 --> 00:04:33,300 dots that keep there, that keep, sorry for the mistake here, that keep 25 24 00:04:33,300 --> 00:04:58,019 millimeters from P. This construction is called circumference. Number three, all 25 00:04:58,019 --> 00:05:06,180 points that keep the same distance from lines R and S. Okay, so in order to place 26 00:05:06,180 --> 00:05:16,319 that, we need to draw from the vertex V, this is the vertex of the angle, these are 27 00:05:16,319 --> 00:05:23,819 two intersecting lines, we have two intersecting lines in one angle, so you 28 00:05:23,819 --> 00:05:35,420 place a compass on V and with any radius you draw the arc, you will get two 29 00:05:35,420 --> 00:05:50,899 points one and two and you can change the radius okay the previous one so I'm 30 00:05:50,899 --> 00:06:00,620 going to do or use a bigger one and from one and two look carefully so from one 31 00:06:00,620 --> 00:06:11,680 one arc and with the same radius than than this one from two you have two 32 00:06:11,680 --> 00:06:17,500 intersecting arches. So again, from 1 with any radius, you don't need to use 33 00:06:17,500 --> 00:06:29,800 this one, you can use a different one, 1 and 2. You will get a 0.3 and this 0.3 34 00:06:29,800 --> 00:06:42,959 keep the same distance from R and from S. So, if you connect with the vertex V, you 35 00:06:42,959 --> 00:06:59,769 will get the construction this is it this construction is called angle by 36 00:06:59,769 --> 00:07:15,699 sector just divides the angle into okay number four locus of all points that 37 00:07:15,699 --> 00:07:25,560 keep 40 millimeters from line R okay good and we are going to measure the 40 38 00:07:25,560 --> 00:07:38,829 millimeters in here we are going to place a square or bevel 90 degrees in 39 00:07:38,829 --> 00:08:04,009 any place on R. We draw the perpendicular and measure, we'll measure 40, that's it. 40 00:08:04,009 --> 00:08:15,889 Erase the rest of the segment, the straight line. We are going to need only 40 and we 41 00:08:15,889 --> 00:08:23,250 We need arrowheads like before, like on the radius, but we need two. 42 00:08:23,250 --> 00:08:31,350 On radius we use one, on measurements we need two arrowheads. 43 00:08:31,350 --> 00:08:43,789 The tip of the arrowhead on 40, this is 40, place the number that way, vertically, and 44 00:08:43,789 --> 00:08:56,990 to the left good and once you have the distance with accuracy place the bevel 45 00:08:56,990 --> 00:09:07,070 or the square on the straight line on our the straight line and the other 46 00:09:07,070 --> 00:09:13,549 ruler is going to be the guide so we are going to draw a parallel keep the ruler 47 00:09:13,549 --> 00:09:19,750 still, and move the square to the tip of the arrowhead. 48 00:09:19,750 --> 00:09:26,669 And you will get, draw the parallel, and that's it. 49 00:09:26,669 --> 00:09:36,830 And name the parallel as a straight line S in lower case. 50 00:09:36,830 --> 00:09:40,309 And the construction is called.