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If the angles of a triangle are in the raitio 4:5:9. Find all the angles of a the...

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hmshah98knic | Student, Grade 9 | Honors

Posted June 24, 2012 at 6:51 AM via web

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If the angles of a triangle are in the raitio 4:5:9. Find all the angles of a the triangle .

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justaguide | College Teacher | (Level 2) Distinguished Educator

Posted June 24, 2012 at 7:09 AM (Answer #1)

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The sum of the angles of a triangle is 180 degrees. As the ratio of the angles of the triangle is 4:5:9 they can be taken to be 4x, 5x and 9x. 4x + 5x + 9x = 180

=> 18x = 180

=> x = 10

This gives the angles of the triangle as 40, 50 and 90 degrees.

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manurbhav | Student , Grade 9 | eNotes Newbie

Posted June 24, 2012 at 8:33 AM (Answer #2)

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the sum of all angles of triangle =180

let one angle = x

so, all angles = 4x, 5x, 9x

According to question

4x + 5x+ 9x=180

18x= 180

x= 180/18

x= 10

angles=(4*10), (5*10), (9*10)

         =40,50, 90

 

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vaaruni | High School Teacher | Salutatorian

Posted June 24, 2012 at 10:24 AM (Answer #3)

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Given : The angles of a triangle are in the ratio 4:5:9.

Let the angles be 4x , 5x, and 9x

4x + 5x + 9x = 180 [ sum of the angles of a triangle = 180 degrees ] 

Or,   18x = 180

Or,    x = 180/18 = 10

  i.e.  x = 10 

4x = 4*10 = 40    i.e.  4x = 40

5x = 5*10 = 50    i.e   5x = 50

9x = 9*10 = 90    i.e.  9x = 90 

therefore angles are  40 degrees, 50 degrees and 90 degrees  Answer

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