direktori wisata tirta 2012 (12)

8/12/2019 Direktori Wisata Tirta 2012 (12)

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Dhaval Bathia


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Dhaval Bathia

Using the Pythagoras theorem, we can find the

length of the third side of a triangle, when any two

sides are given to us


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Dhaval Bathia

3

4

?

In the above triangle, one side is 3units and the other

side is 4units..

Using the Pythagoras Theorem, (AB)2+ (BC)2= (AC)2

we can find the value of the third side as 5units

A

B C


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Dhaval Bathia

But what will you do if only one side of the triangle is

revealed to you ?

Can you find the other two ?

Suppose they ask a question saying that in a triangle,length AB is 9 units....

A

Can you find lengths BC and AC ?

9

BC


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Dhaval Bathia

This is precisely what we are going to study in this

presentation

How to find two sides of a triangle, where only one is given

to you

In school, we are taught how to find 1 side when 2 are given.Here, we will see how to find 2 sides, when 1 is given !

Our study is divided into two parts:

First, we will see how to use the technique for odd numbers

Next, we will see how to use the technique for even numbers


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Dhaval Bathia

ODD NUMBERS

This technique can be used for odd numbers like 3, 5, 7 etc.

Basically, there are three steps:

First, Square the number

Next, divide it by 2

Finally, Round it off


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Dhaval Bathia

Let us have a look at an example :

A

3

B C

We use three steps :

A)Square the number

B) Divide it by 2

C) Round it off

Square of 3is 9

9divided by 2 is 4.5

When 4.5is rounded off, we

get 4(Smaller number) and

5(bigger number)


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Dhaval Bathia

A

B C

3

4

5

The number 3was given to us.

We obtained values 4and 5

Thus, (3-4-5) form a combined triplet !


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Dhaval Bathia

Let us have a look at another example:Suppose one of the given values is 9

Let us find the other 2


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Dhaval Bathia

A

9

B C


A)Square the number

B) Divide it by 2

C) Round it off

Square of 9is 81


When 40.5is rounded off,

we get 40(Smaller number)

and 41(bigger number)


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Dhaval Bathia

A

B C

9

40

41





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Dhaval Bathia

Let us take a last example example:Suppose one of the given values is 7

Let us find the other two


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Dhaval Bathia

A

7

B C


A)Square the number

B) Divide it by 2

C) Round it off

Square of 7is 49


When 24.5is rounded off,

we get 24(Smaller number)

and 25(bigger number)


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Dhaval Bathia

A

B C

7

24

25





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Dhaval Bathia

This technique can be used for odd numbers like 6, 10, 12 etc.

In this case, we convert EVEN numbers to ODD numbers, use the

same technique for ODD numbers and re-convert the odd numbers

back to even numbers

EVEN NUMBERS


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Dhaval Bathia

Q) Find the two sides of a triangle, if one side is 6 units

Ans :

We divide 6 by 2 and get an odd number 3

Now, we follow the same procedure explained with odd

numbers and get a triplet as (3-4-5)

Since we had divided by 2, we now multiply all values (3-4-5) by 2 and get the answer as (6-8-10)

Thus, if one value is 6, the other 2 values will be 8 and 10

direktori wisata tirta 2012 (12)

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