1
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Find the sum of 15 + ( -46 ) + 29

2
00:00:05,921 --> 00:00:08,568
So lets think about the first part over here

3
00:00:08,568 --> 00:00:16,324
We have 15 + ( -46), we will worry about +29 later

4
00:00:16,324 --> 00:00:27,469
So lets do 15 + ( -46)

5
00:00:27,469 --> 00:00:34,900
So we draw a number line

6
00:00:34,900 --> 00:00:38,011
so we can visualize what is going on.

7
00:00:38,011 --> 00:00:47,578
Let me put 0 and we're starting with 15

8
00:00:51,246 --> 00:00:54,915
15 could be right over here and draw a big fat arrow to signify this is 15

9
00:00:54,915 --> 00:00:59,466
15 has an absolute value of 15

10
00:00:59,466 --> 00:01:04,064
so the length of this arrow would be 15

11
00:01:04,064 --> 00:01:07,500
so lets add -46 to 15, this is the same thing as

12
00:01:07,500 --> 00:01:14,048
15-46, which means we are going to move

13
00:01:14,048 --> 00:01:23,569
46 places to the left of 15.

14
00:01:23,569 --> 00:01:30,860
So we are starting with 15 and going to go 46

15
00:01:30,860 --> 00:01:40,380
to the left.The length of this arrow is going to be 46.

16
00:01:40,380 --> 00:01:44,745
We are going to the left which means it is negative.

17
00:01:44,745 --> 00:01:48,878
We are going to end up at some point over here.

18
00:01:48,878 --> 00:01:55,798
This point is 0 and this is to the left of 0

19
00:01:55,798 --> 00:02:04,250
can you think of the absolute value of this.

20
00:02:04,250 --> 00:02:09,498
This yellow arrow has the length of 15 and this orange arrow is the length of 46

21
00:02:09,498 --> 00:02:14,002
The blue arrow that i am going to draw

22
00:02:14,002 --> 00:02:28,074
is what we have to figure out.

23
00:02:28,074 --> 00:02:31,139
How can we figure it.

24
00:02:31,139 --> 00:02:33,739
we need to find the difference of the

25
00:02:33,739 --> 00:02:35,411
orange arrow & the yellow arrow.

26
00:02:35,411 --> 00:02:43,817
The difference between 46 & 15

27
00:02:43,817 --> 00:02:48,879
is 31.The length of the blue arrow is 31

28
00:02:48,879 --> 00:02:57,145
and it is 31 to the left of 0 and is going to be -31

29
00:02:57,145 --> 00:03:00,721
So we know the first part is -31 and to that

30
00:03:00,721 --> 00:03:08,662
we are going to add 29.

31
00:03:08,662 --> 00:03:12,006
So what does that mean. It means we start at -31

32
00:03:12,006 --> 00:03:16,418
and go 29 to the right

33
00:03:16,418 --> 00:03:30,814
so let me draw an arrow.

34
00:03:30,814 --> 00:03:41,960
so we are moving 29 to the right.

35
00:03:41,960 --> 00:03:44,653
how are we going to figure out what this is

36
00:03:44,653 --> 00:03:52,548
so this going to land us right over here.

37
00:03:52,548 --> 00:03:56,820
once again we need to visualize

38
00:03:56,820 --> 00:04:05,133
we are starting from -31 and adding 29

39
00:04:05,133 --> 00:04:08,988
since we are adding a number less than -31

40
00:04:08,988 --> 00:04:13,632
we are going to have a number less than 0

41
00:04:13,632 --> 00:04:16,650
and is going to be a negative number

42
00:04:16,650 --> 00:04:20,467
how to figure out the absolute value of that number

43
00:04:20,467 --> 00:04:33,090
we need to figure out what the white part is

44
00:04:33,090 --> 00:04:37,548
31-29 is going to give us the length of the white part

45
00:04:37,548 --> 00:04:44,746
and is going to be negative as it is to the left of 0

46
00:04:44,746 --> 00:04:57,332
31-29 = 2 and since it going

47
00:04:57,332 --> 00:05:10,381
to be to the left of 0, it is going to be -2

48
00:05:10,381 --> 00:05:13,307
the length of the white part

49
00:05:13,307 --> 00:05:22,641
is 2.and since it is to the left of 0 it is -2

50
00:05:22,641 --> 99:59:59,999
final answer is -2