1 00:00:00,680 --> 00:00:07,470 Let's do this question, BQ is a diameter of the circle, or as is parallel to BQ, B are is equal to 2 00:00:07,500 --> 00:00:09,290 askew is equal to six centimeter. 3 00:00:09,320 --> 00:00:10,640 All right, find out. 4 00:00:10,650 --> 00:00:14,890 Just given that the radius of the circle is five centimeter was the video. 5 00:00:15,050 --> 00:00:17,450 Give it a try and then let's do it together. 6 00:00:17,870 --> 00:00:18,290 All right. 7 00:00:18,290 --> 00:00:18,780 We're back. 8 00:00:18,890 --> 00:00:20,000 Let's do it together. 9 00:00:20,150 --> 00:00:20,870 Now, over here. 10 00:00:20,870 --> 00:00:22,670 BQ is a diameter, right? 11 00:00:22,790 --> 00:00:25,160 And we know that the radius is five centimeter. 12 00:00:25,340 --> 00:00:27,520 Therefore, P Q is equal to two in the five. 13 00:00:27,530 --> 00:00:28,970 That gives you 10 centimeter. 14 00:00:29,270 --> 00:00:29,710 All right. 15 00:00:29,900 --> 00:00:33,400 Now it's given PR is equal to askew is equal to six centimeter. 16 00:00:33,590 --> 00:00:34,930 Let's mark that over here. 17 00:00:35,360 --> 00:00:38,090 So Paris six and Q is six. 18 00:00:38,370 --> 00:00:38,770 All right. 19 00:00:38,900 --> 00:00:42,680 Now let's join B and S all right. 20 00:00:42,830 --> 00:00:44,780 And you can see that angle P. 21 00:00:45,110 --> 00:00:47,770 Q is equal to 90 degrees, right? 22 00:00:47,820 --> 00:00:48,700 Why is that so? 23 00:00:48,830 --> 00:00:55,100 Because P Q is the diameter and we know that angle sub-standard by the diameter is the right angle to 24 00:00:55,100 --> 00:00:57,540 angle P Q is equal to 90 degrees. 25 00:00:57,890 --> 00:00:58,280 All right. 26 00:00:58,430 --> 00:01:05,450 Now in right angle triangle P Askew over here we have Pexton and ask us six. 27 00:01:05,720 --> 00:01:12,680 So using Pythagoras Theorem we can find a square root of ten squared minus six square that gives you 28 00:01:12,680 --> 00:01:16,610 sixty four square root of sixty four which is equal to eight already. 29 00:01:16,760 --> 00:01:17,960 So we got both. 30 00:01:18,110 --> 00:01:27,470 Now let the height through vertex is of triangle P, Q, B over here and let it be attached to the area 31 00:01:27,470 --> 00:01:28,580 of triangle pieces. 32 00:01:28,580 --> 00:01:32,840 Q can be found this half in two pieces into a skew. 33 00:01:32,840 --> 00:01:34,800 Right, because this angle is ninety degrees. 34 00:01:34,970 --> 00:01:37,130 We know area is half in the base in the height. 35 00:01:37,370 --> 00:01:42,860 But if I take a skew as the base as will be the height because this angle is ninety degrees to area 36 00:01:42,860 --> 00:01:50,690 of triangle Q is equal to half in the piece in the Q and if I take P Q as the base then this over here 37 00:01:50,690 --> 00:01:52,130 that is X is the height. 38 00:01:52,290 --> 00:01:55,670 So this same area will be equal to half in the etching. 39 00:01:55,670 --> 00:02:02,780 The P q now over here I have is equal to eight and askew is equal to six. 40 00:02:02,900 --> 00:02:03,320 Right. 41 00:02:03,440 --> 00:02:04,940 And P Q is equal to ten. 42 00:02:04,940 --> 00:02:06,890 So let me substitute that over here. 43 00:02:07,100 --> 00:02:11,810 So I get eight in the six is equal to each in 210 or solving it. 44 00:02:11,810 --> 00:02:13,910 I get it is equal to four point eight. 45 00:02:14,390 --> 00:02:14,870 All right. 46 00:02:15,080 --> 00:02:16,190 Now let's proceed. 47 00:02:18,120 --> 00:02:22,990 Let me drop a perpendicular from our also so that this one over here. 48 00:02:23,260 --> 00:02:30,460 Now, let me take this point, this point and let this distance AQ be equal to X. 49 00:02:30,840 --> 00:02:36,360 Now, consider the right angle triangle s AQ because this is a 90 degree angle. 50 00:02:36,360 --> 00:02:40,670 Right, because we dropped the perpendicular now in right angle triangle essay. 51 00:02:40,680 --> 00:02:47,040 Q You can see that skew is the hypotenuse and one side is edge and the other side is X. 52 00:02:47,230 --> 00:02:51,600 So six square is equal to eight squared plus X square. 53 00:02:51,930 --> 00:02:57,840 Now using this you can find that X squared is equal to six squared, minus four point eight squared 54 00:02:57,840 --> 00:03:00,420 because we found that it is equal to four point eight. 55 00:03:00,690 --> 00:03:08,080 Now remember is squared minus B square is equal to A, minus B into A plus B, right. 56 00:03:08,250 --> 00:03:10,340 So you must have known that in your algebra. 57 00:03:10,470 --> 00:03:16,940 So square is a square minus because it minus being A plus B, so I use that to solve this faster. 58 00:03:17,070 --> 00:03:21,940 So this becomes six minus four point eight in the six plus four point eight. 59 00:03:22,110 --> 00:03:24,750 That is one point two in two, ten point eight. 60 00:03:25,080 --> 00:03:25,520 All right. 61 00:03:25,890 --> 00:03:29,280 Let me make some space over here now on solving this. 62 00:03:29,280 --> 00:03:36,210 You can find that X is equal to square root of twelve point nine six, and that is equal to approximately 63 00:03:36,210 --> 00:03:37,200 three point six. 64 00:03:37,860 --> 00:03:43,740 In a previous video in the section on numbers, we had seen how to find the approximate square root. 65 00:03:43,740 --> 00:03:43,980 Right. 66 00:03:44,130 --> 00:03:47,040 If you don't remember that, please go and refer that variable. 67 00:03:47,160 --> 00:03:49,700 So that will help you to find this as three point six. 68 00:03:49,890 --> 00:03:54,780 Let me quickly summarize it over here, then you're screwed over here is square root of nine. 69 00:03:54,790 --> 00:03:55,980 That gives you three, right? 70 00:03:56,130 --> 00:04:00,440 So this is approximately square root of thirteen twelve point nine six. 71 00:04:00,630 --> 00:04:03,980 And that is approximately nine plus four right now. 72 00:04:03,990 --> 00:04:06,780 Square root of nine is three and you are left with four. 73 00:04:06,900 --> 00:04:12,120 So this becomes three plus four, divided by two in three D three. 74 00:04:12,120 --> 00:04:12,400 Right. 75 00:04:12,570 --> 00:04:14,370 So that's three plus four by six. 76 00:04:14,460 --> 00:04:16,950 And that gives you three point six. 77 00:04:17,610 --> 00:04:18,030 Right. 78 00:04:18,180 --> 00:04:20,490 Because four by six point six. 79 00:04:20,490 --> 00:04:21,850 Six six extra. 80 00:04:21,870 --> 00:04:23,480 So I take you this point six. 81 00:04:23,840 --> 00:04:24,240 All right. 82 00:04:24,570 --> 00:04:26,090 Let me make some space over here. 83 00:04:27,070 --> 00:04:33,010 So we have found that the value of X is approximately three point six. 84 00:04:33,490 --> 00:04:39,670 All right, now we need to find our S from this diagram, you can see that Otter's is equal to that 85 00:04:39,670 --> 00:04:42,750 is equal minus X, minus X. 86 00:04:42,760 --> 00:04:48,250 This also will be x rayed because these two triangles are congruent because this is also six is also 87 00:04:48,250 --> 00:04:48,640 six. 88 00:04:48,640 --> 00:04:48,940 Right. 89 00:04:49,160 --> 00:04:49,960 So this is also X. 90 00:04:49,960 --> 00:04:52,130 This is also X, so 10 minus two. 91 00:04:52,690 --> 00:04:55,420 That is ten minus two in the three point six. 92 00:04:55,600 --> 00:04:57,910 We'll give you the value of our X. 93 00:04:58,880 --> 00:05:04,610 And that is equal to two point eight centimeter, and that is the solution to this question.