1
00:00:00,690 --> 00:00:04,990
我们已知射线OL与射线ON垂直

2
00:00:04,990 --> 00:00:07,640
所以OL垂直ON

3
00:00:07,640 --> 00:00:10,020
所以这个角是一个直角

4
00:00:10,020 --> 00:00:11,600
或者说是一个90度的角

5
00:00:11,600 --> 00:00:15,190
他们告诉我们角LOM

6
00:00:15,190 --> 00:00:18,060
是2x+46

7
00:00:18,060 --> 00:00:22,360
所以，这个角，LOM

8
00:00:22,360 --> 00:00:24,937
是等于2x+46

9
00:00:28,100 --> 00:00:31,000
之后他们告诉我们角MON

10
00:00:31,000 --> 00:00:34,480
等于3x-6

11
00:00:34,480 --> 00:00:38,440
所以这个角是3x-6

12
00:00:38,440 --> 00:00:40,730
他们让我们去求角MON的值

13
00:00:40,730 --> 00:00:43,339
所以我们需要找到这个角

14
00:00:43,339 --> 00:00:45,380
我们如果知道x是多少，就能找到这个角

15
00:00:45,380 --> 00:00:47,505
如果我们知道x是什么，
那么着个角

16
00:00:47,505 --> 00:00:48,720
就是3x-6

17
00:00:48,720 --> 00:00:50,330
我们知道一个条件

18
00:00:50,330 --> 00:00:52,020
如果我们把这两个角度加起来

19
00:00:52,020 --> 00:00:53,710
他们是临近角

20
00:00:53,710 --> 00:00:56,880
他们外围的射线组成了一个直角

21
00:00:56,880 --> 00:01:00,130
所以这两个角加起来是90度

22
00:01:00,130 --> 00:01:02,820
我们可以假设我们用的是角度数

23
00:01:02,820 --> 00:01:12,990
所以说2x+46+3x-6

24
00:01:12,990 --> 00:01:17,410
加起来等于90度

25
00:01:17,410 --> 00:01:19,610
这两个角是互补角

26
00:01:19,610 --> 00:01:21,830
所以加起来是90度

27
00:01:21,830 --> 00:01:23,164
加起来是90度

28
00:01:23,164 --> 00:01:24,580
那么，我们只需要化简

29
00:01:24,580 --> 00:01:25,460
我们有个2x

30
00:01:25,460 --> 00:01:26,690
还有个3x

31
00:01:26,690 --> 00:01:29,720
加起来就是5x

32
00:01:29,720 --> 00:01:32,419
然后我们有46

33
00:01:32,419 --> 00:01:33,710
之后减去6

34
00:01:33,710 --> 00:01:36,700
所以就等于5x+40=90

35
00:01:39,220 --> 00:01:41,550
等式两边减去40

36
00:01:41,550 --> 00:01:42,450
我们这么做

37
00:01:42,450 --> 00:01:45,060
减去40

38
00:01:45,060 --> 00:01:49,140
然后左边就剩下了5x

39
00:01:49,140 --> 00:01:53,220
然后右手边是50

40
00:01:53,220 --> 00:01:55,950
接下来等式两边除以5

41
00:01:55,950 --> 00:02:00,630
我们就剩下x=10

42
00:02:00,630 --> 00:02:02,240
那么我们的答案不是10

43
00:02:02,240 --> 00:02:04,280
我们刚找到x是什么

44
00:02:04,280 --> 00:02:07,470
他们问我们角MON的值

45
00:02:07,470 --> 00:02:11,770
我们已经知道角MON

46
00:02:11,770 --> 00:02:23,300
等于3x-6，
等于3乘以10减去6

47
00:02:23,300 --> 00:02:27,430
减去6用绿色表示

48
00:02:27,430 --> 00:02:32,550
等于24度