30. One of the angle of a triangle is equal to the sum of the other two angles. If the ratio of the other
two angles 4:5, the

1 thought on “30. One of the angle of a triangle is equal to the sum of the other two angles. If the ratio of the other<br />two angles 4:5, the”

1. Answer:

   If in your options there is 40°,50°,90° that option is right.

   Step-by-step explanation:

   Let the two angles of the triangle be 4x and 5x.

   Then, as per the question, we know

   third angle =4x+5x=9x

   We know that sum of all the angles of a triangle is 180

   ∘

   .

   ∴4x+5x+9x=180

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   ⇒18x=180

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   ⇒x=10

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   ….[On dividing both sides by 18]

   So, first angle = 4x

   ∘

   = 4×10

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   =40

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   ,

   second angle = 5x

   ∘

   = 5×10

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   =50

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   and

   and third angle = 9x

   ∘

   = 9×10

   ∘

   =90

   ∘

   This is the right answer for your question.

   Reply