English

In the given figure, the value of x is ______. 65°, 80°, 95°, 120°

Advertisements
Advertisements

Question

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

Options

  • 65°

  • 80°

  • 95°

  • 120°

MCQ
Fill in the Blanks
Advertisements

Solution

In the given figure, the value of x is 120°.

Explanation:

In the given figure, we need to find the value of x

Here, according to the angle sum property of the triangle

In ΔABD

∠BAD + ∠DBA + ∠ADB = 180°

55° + ∠DBA + 25° = 180°

80 + ∠DBA = 180°

∠DBA = 180° - 80°

∠DBA  = 100°

∠DBA = 100°

Also, ABC is a straight line. So, using the property, “angles forming a linear pair are supplementary”, we get,

∠DBA + ∠DBC = 180°

100 + ∠DBC = 180°

∠DBC = 180° - 100°

∠DBC = 80°

Further, using the property, “exterior angle of a triangle is equal to the sum of two opposite interior angles”, we get

ext. ∠DOC + ∠OBC + ∠OCB

 x = 80°+ 40°

x = 120°

Thus, x = 120°

shaalaa.com
  Is there an error in this question or solution?
Chapter 11: Triangle and its Angles - Exercise 11.4 [Page 28]

APPEARS IN

R.D. Sharma Mathematics [English] Class 9
Chapter 11 Triangle and its Angles
Exercise 11.4 | Q 21 | Page 28

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

ABC is an isosceles triangle in which altitudes BE and CF are drawn to equal sides AC and AB respectively (see the given figure). Show that these altitudes are equal.


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


If the base of an isosceles triangle is produced on both sides, prove that the exterior angles so formed are equal to each other. 


In an isosceles triangle, if the vertex angle is twice the sum of the base angles, calculate the angles of the triangle. 


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.  

 


Prove that each angle of an equilateral triangle is 60°. 


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

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


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

Of all the line segments that can be drawn from a point to a line not containing it, the perpendicular line segment is the shortest one. 


Fill in the blank to make the following statement true. 

In a right triangle the hypotenuse is the .... side. 


Fill in the blank to make the following statement true. 

The sum of three altitudes of a triangle is ..... than its perimeter. 


Write the sum of the angles of an obtuse triangle.


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, if AB ⊥ BC. then x =


In the given figure, for which value of x is l1 || l2?


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


It is given that ∆ABC ≅ ∆FDE and AB = 5 cm, ∠B = 40° and ∠A = 80°. Then which of the following is true?


In ∆PQR, if ∠R > ∠Q, then ______.


AD is a median of the triangle ABC. Is it true that AB + BC + CA > 2AD? Give reason for your answer.


Is it possible to construct a triangle with lengths of its sides as 9 cm, 7 cm and 17 cm? Give reason for your answer.


Show that in a quadrilateral ABCD, AB + BC + CD + DA < 2(BD + AC)


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×