geometry questions

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praveen_84's picture
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What is the vaule of  angle(ABC) angle (CBE) in the following figure


In the below figure AB = 9 cms BC = 3 cms CE = 14 cms EF = 4 cm.
If the line CE touches the circle at D. Find
the lengths of
(a) CD
(b) ED
(c) FG

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geometry

.in first one angle at centre is twice at perimetre.so this is logic.in second one use the simple formula. answerof first one is 50 and 130.

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anita1's picture
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Angle (APC) = Angle (ADC) =

Angle (APC) = Angle (ADC) = Half of angle AOC = 50
Angle made at center is twice the angle

Now angle (ABC) + angle (APC) = 180 (sum of opposite sides of a circular quadrilateral)
=> Angle (ABC) = 130

And angle (CBE) + angle (ABC) = 180
So angle (CBE) = 50

 

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Q2.

CB x CA = CD2

=> CD= 3 x 12 = 36

=> CD = 6

As CE = 14

=>DE = 8

Again DE2 = EF x EG

=> EG = 64/4 = 16

=> GF = 16 - 4 = 12

shabash_23's picture
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Q1         Take major

Q1

  

     Take major arc APDC.  Angle subtended by this arc at centre = 360-100 = 260.

     therefore angle subtended by this arc at point B i.e angle ABC = 130.

     Obviously angle CBE is 50.

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ryan's picture
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q1

the ans is 130 and 50 deg.

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ryan's picture
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q2

the answers are 6 , 8 , 12 respectively

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