English

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

Advertisements
Advertisements

Question

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

Options

  • 45°

  •  95°

  • 135°

  • 90°

MCQ
Advertisements

Solution

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°

shaalaa.com
  Is there an error in this question or solution?
Chapter 11: Triangle and its Angles - Exercise 11.4 [Page 29]

APPEARS IN

RD Sharma Mathematics [English] Class 9
Chapter 11 Triangle and its Angles
Exercise 11.4 | Q 25 | Page 29

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

ΔABC is an isosceles triangle in which AB = AC. Side BA is produced to D such that AD = AB (see the given figure). Show that ∠BCD is a right angle.


In Figure AB = AC and ∠ACD =105°, find ∠BAC.  


Prove that the medians of an equilateral triangle are equal. 


P is a point on the bisector of an angle ∠ABC. If the line through P parallel to AB meets BC at Q, prove that triangle BPQ is isosceles.  

 


ABC is a right angled triangle in which ∠A = 90° and AB = AC. Find ∠B and ∠C. 

 


ABC is a triangle in which BE and CF are, respectively, the perpendiculars to the sides AC and AB. If BE = CF, prove that ΔABC is isosceles  


Which of the following statements are true (T) and which are false (F): 

The two altitudes corresponding to two equal sides of a triangle need not be equal. 


Fill the blank in the following so that the following statement is true. 

Angle opposite to equal sides of a triangle are ..... 


Fill the blank in the following so that the following statement is true. 

If altitudes CE and BF of a triangle ABC are equal, then AB = .... 


Fill in the blank to make the following statement true. 

If two angles of a triangle are unequal, then the smaller angle has the........ side opposite to it. 


In the given figure, the sides BC, CA and AB of a Δ ABC have been produced to D, E and F respectively. If ∠ACD = 105° and ∠EAF = 45°, find all the angles of the Δ ABC.


If the angles A, B and C of ΔABC satisfy the relation B − A = C − B, then find the measure of ∠B.


In the given figure, what is the value of x?


In the given figure, the value of x is ______.


In a ΔABC, ∠A = 50° and BC is produced to a point D. If the bisectors of ∠ABC and ∠ACDmeet at E, then ∠E =


The side BC of ΔABC is produced to a point D. The bisector of ∠A meets side BC in L. If ∠ABC = 30° and ∠ACD = 115°, then ∠ALC = ______.


In the given figure, if l1 || l2, the value of x is


In triangles ABC and PQR, AB = AC, ∠C = ∠P and ∠B = ∠Q. The two triangles are ______.


In the following figure, D and E are points on side BC of a ∆ABC such that BD = CE and AD = AE. Show that ∆ABD ≅ ∆ACE.


Show that in a quadrilateral ABCD, AB + BC + CD + DA > AC + BD


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×