मराठी

In ΔABC, AD is the perpendicular bisector of BC (see the given figure). Show that ΔABC is an isosceles triangle in which AB = AC.

Advertisements
Advertisements

प्रश्न

In ΔABC, AD is the perpendicular bisector of BC (see the given figure). Show that ΔABC is an isosceles triangle in which AB = AC.

बेरीज
Advertisements

उत्तर

Since AD is the bisector of BC.

∴ BD = CD

Now, in △ABD and △ACD, we have

AD = DA           ...[Common]

∠ADB = ∠ADC     ...[Each 90°]

BD = CD             ...[Proved above]

∴ △ABD ≌ △ACD       ...[By SAS congruence]

⇒ AB = AC         ...[By Corresponding parts of congruent triangles]

Thus, △ABC is an isosceles triangle.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 7: Triangles - EXERCISE 7.2 [पृष्ठ ९७]

APPEARS IN

एनसीईआरटी Mathematics [English] Class 9
पाठ 7 Triangles
EXERCISE 7.2 | Q 2. | पृष्ठ ९७

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

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

  1. ΔABE ≅ ΔACF
  2. AB = AC, i.e., ABC is an isosceles triangle.


In Fig. 10.40, it is given that RT = TS, ∠1 = 2∠2 and ∠4 = 2∠3. Prove that ΔRBT ≅ ΔSAT 

  


In a ΔABC, if ∠A=l20° and AB = AC. Find ∠B and ∠C. 


In a ΔABC, if AB = AC and ∠B = 70°, find ∠A. 


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

 


In ΔABC, side AB is produced to D so that BD = BC. If ∠B = 60° and ∠A = 70°, prove that: (i) AD > CD (ii) AD > AC 


O is any point in the interior of ΔABC. Prove that
(i) AB + AC > OB + OC
(ii) AB + BC + CA > OA + QB + OC 
(iii) OA + OB + OC >` 1/2`(AB + BC + CA) 


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

Sum of any two sides of a triangle is greater than the third side. 

 


Fill in the blank to make the following statement true. 

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


Fill in the blank to make the following statement true.  

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


In the given figure, what is y in terms of x?


In the given figure, AB and CD are parallel lines and transversal EF intersects them at Pand Q respectively. If ∠APR = 25°, ∠RQC = 30° and ∠CQF = 65°, then


The base BC of triangle ABC is produced both ways and the measure of exterior angles formed are 94° and 126°. Then, ∠BAC =


In ∆ABC, AB = AC and ∠B = 50°. Then ∠C is equal to ______.


In ∆ABC, BC = AB and ∠B = 80°. Then ∠A is equal to ______.


In ∆PQR, ∠R = ∠P and QR = 4 cm and PR = 5 cm. Then the length of PQ is ______.


Two sides of a triangle are of lengths 5 cm and 1.5 cm. The length of the third side of the triangle cannot be ______.


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 8 cm, 7 cm and 4 cm? Give reason for your answer.


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


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×