1
00:00:00,620 --> 00:00:06,830
Let's do this question, find the perpendicular distance of point B, which is three comma, minus four

2
00:00:07,100 --> 00:00:10,910
from the line three plus four Y minus five is equal to zero.

3
00:00:11,150 --> 00:00:11,560
All right.

4
00:00:11,570 --> 00:00:14,670
Pause the video, give it a try and then let's do it together.

5
00:00:15,050 --> 00:00:15,470
All right.

6
00:00:15,470 --> 00:00:15,930
We are back.

7
00:00:15,950 --> 00:00:16,870
Let's do it together.

8
00:00:16,870 --> 00:00:19,430
At the given point is three comma minus four.

9
00:00:19,580 --> 00:00:23,470
And the line is three X plus four Y minus five is equal to zero.

10
00:00:23,480 --> 00:00:23,800
Right.

11
00:00:23,960 --> 00:00:26,290
And we need to find the perpendicular distance.

12
00:00:26,540 --> 00:00:27,860
Now we know how to do that.

13
00:00:27,980 --> 00:00:29,090
The distance would be.

14
00:00:30,160 --> 00:00:36,490
Three in the three, plus four in the minus four, minus five divided by root of three squared plus

15
00:00:36,490 --> 00:00:37,130
four square.

16
00:00:37,260 --> 00:00:37,510
Right.

17
00:00:37,750 --> 00:00:41,850
Well here we substitute a three comma minus four into this equation.

18
00:00:42,070 --> 00:00:44,770
So instead of X, we have three, right?

19
00:00:44,920 --> 00:00:47,290
Instead of white, we have minus four.

20
00:00:47,380 --> 00:00:50,470
And then we have the remaining part of this equation.

21
00:00:50,710 --> 00:00:55,000
So and in the denominator, we have a lot of square, let's be square.

22
00:00:55,000 --> 00:00:58,360
And three and four is B, right.

23
00:00:58,570 --> 00:01:05,830
So this simplifies to nine minus 16, minus five divided by five, which is equal to minus twelve by

24
00:01:05,830 --> 00:01:06,220
five.

25
00:01:06,430 --> 00:01:08,160
Now the distance cannot be negative.

26
00:01:08,170 --> 00:01:09,760
So you always take the positive.

27
00:01:09,940 --> 00:01:12,540
That's what you mean when you take the model over here.

28
00:01:12,550 --> 00:01:15,300
Right there is equal to twelve by five.

29
00:01:15,460 --> 00:01:17,050
And that is your answer.