मराठी

If the Bisectors of the Acute Angles of a Right Triangle Meet at O, Then the Angle at O Between the Two Bisectors is

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प्रश्न

If the bisectors of the acute angles of a right triangle meet at O, then the angle at Obetween the two bisectors is

पर्याय

  • 45°

  •  95°

  • 135°

  • 90°

MCQ
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उत्तर

In the given problem, bisectors of the acute angles of a right angled triangle meet at O. We need to find  ∠AOC.

Now, using the angle sum property of a triangle

In ΔABC

∠A + ∠B + ∠C = 180° 

90° + ∠A+ ∠C = 180°

        ∠A + ∠C = 90°   ..............(1)

Now, further multiplying each of the term by  1/2in (1)

`1/2 ∠A + 1/2 ∠C = 1/2 90°`

∠OAC + ∠ACO = 45°

Also, applying angle sum property of a triangle

In ΔAOC

∠OAC + ∠ACO + ∠AOC = 180°

                   45° + ∠AOC = 180°

                            ∠AOC = 180° - 45° 

                                      = 135°

Thus, ∠AOC = 135°

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पाठ 11: Triangle and its Angles - Exercise 11.4 [पृष्ठ २९]

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आर.डी. शर्मा Mathematics [English] Class 9
पाठ 11 Triangle and its Angles
Exercise 11.4 | Q 25 | पृष्ठ २९

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

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