1
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Let's do this question, find the area enclosed by this equation over here.

2
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Now remember, Gmod means you take the positive value.

3
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For example, more of minus two gives you two.

4
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More of two also gives you two to more means.

5
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Always take the positive, irrespective of the given number being negative or positive.

6
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All right.

7
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Now let's proceed over here.

8
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You have given your given this equation that is four more X plus five more weigh less than equal to

9
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twenty.

10
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Right now, this over here represents four straight lines.

11
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Now, let's see how that is.

12
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Let me mention it over here.

13
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All right, now let me right the four straight lines that are represented by this equation, how do

14
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you get them?

15
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You either take excess, positive or negative can be positive or negative and y also can be positive

16
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or negative.

17
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That's two ways.

18
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And this is also two ways.

19
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So two in the two, that's how you get four straight lines.

20
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Let's write them over here.

21
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Or X plus five is equal to 20 over here.

22
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Both of them are taken as positive or into minus X, plus five is equal to twenty.

23
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We we this one is negative and this is positive.

24
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And then you have four X plus five into minus way.

25
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This is positive.

26
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This is negative.

27
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And over here you have four minus X, plus five minus Y is equal to twenty where both are taken as negative.

28
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So these four lines are represented by this equation over here.

29
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Now remember, I'm taking it as equal to to get the border in this equation over here.

30
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It's mentioned as less than equal to.

31
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Let's see what the implication is.

32
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Now, first, let me start with plotting these four equations that we have arrived at.

33
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All right, so I have my access and I plotted like this now how do we do the plotting?

34
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It's very simple.

35
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You just need to find two points to plot a line right now.

36
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Let's take this line over here.

37
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Let's clean this up a little bit, OK?

38
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Now let's take the first one over here.

39
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Over here, four X plus five is equal to zero is equal to 20.

40
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So if X is equal to zero, that's zero plus five is equal to 20.

41
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So Y will be equal to four.

42
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Right.

43
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So zero comma four is one of the points of this line over here.

44
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So let's plot zero comma four.

45
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That's zero zero.

46
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And then on the Y axis, you need to go for units.

47
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That's one, two, three, four.

48
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To this point over here is zero comma four.

49
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Right.

50
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OK, now if I put why as zero, that's four X plus zero is equal to 20, so X is equal to five, right.

51
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So five zero is also lying on this line.

52
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So let's plot that over here.

53
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One, two, three, four, five.

54
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So this is five comma zero.

55
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So I have two points.

56
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And when I join them, I get this line over here.

57
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So if this is the first line, that's this line over here.

58
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All right.

59
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Let's plot the next one over here.

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If I put X is equal to zero, I get why is equal to four.

61
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Right.

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That's zero comma for that at this point over here, which we have already plotted.

63
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And if I put Y is equal to zero, that's minus four.

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X is equal to twenty.

65
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So X has to be equal to minus five.

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So this point over here is minus five from a zero.

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And when I join them I get this line over here.

68
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So if this is line two, that's this line over here.

69
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All right.

70
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Now let's proceed to the third line.

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I have four X plus five in the minus 20.

72
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So when X is equal to zero, Y has to be equal to minus four.

73
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So that's this point over here, which is zero minus four.

74
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Right.

75
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And when Y is equal to zero, X is equal to five.

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That's this point over here.

77
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So this over here is line three.

78
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This is line three.

79
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Right.

80
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And over here, both of them are negative.

81
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So when X is equal to zero, Y has to be minus four.

82
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That's this point.

83
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And when Y is equal to zero, X has to be minus five.

84
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That's this point.

85
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I joined them together and I get nine four over here.

86
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All right.

87
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Now, over here it is mentioned that it's less than equal to.

88
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Right.

89
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So when you plot this line over here, you need to take this line and everything to decide because it

90
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has to be less than that value.

91
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Similarly, when you plot this line, you need to take things that are in this direction.

92
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Right.

93
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And over here, you need to take things that are in this direction.

94
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And for this line, you need to take points that are in this direction.

95
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So you end up getting this shaded region.

96
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And that is what you need to find out, right?

97
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It's mentioned find the area enclosed by this equation over here.

98
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This is the area that you need to find out right now.

99
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Let me clean this up a little bit so that we proceed.

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We have seen how to plot these lines and find the enclosed area that we are trying to find out geometrically.

101
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We have represented it on the access all.

102
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Now, what are these four points?

103
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Remember, we found them out, right?

104
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This is five zero zero four minus five zero and zero minus four.

105
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Now we just need to find this area.

106
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Now you can see that over here, this right angled triangle as sites or units over here and five units

107
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over here.

108
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Right.

109
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And over here.

110
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Also, this right angled triangle has four and five units similar to this one also has four units over

111
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here and five units over here.

112
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This one also has four units over here and five units over here.

113
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So you just need to find one area of a triangle and multiply it with four.

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Now, we know area of this triangle is half base in the height.

115
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That would be half in two or in five.

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Right to the required area.

117
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That is this area over here would be four times off into four and five.

118
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And that gives you 40 units square as the area.

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And that is your answer.
