English

In δAbc, If ∠A = 40° and ∠B = 60°. Determine the Longest and Shortest Sides of The Triangle.

Advertisements
Advertisements

Question

In ΔABC, if ∠A = 40° and ∠B = 60°. Determine the longest and shortest sides of the triangle. 

 

Advertisements

Solution

Given that in , ΔABC  ∠A =40°  and ∠B=60° We have to find longest and shortest side We know that,  

Sum of angles in a triangle180°  

⇒∠A+∠B+∠C=180° 

⇒40°+60°+∠C=180° 

⇒∠C=180° -(40° +60° ) 

      =180° -100° =80°  

∴∠C = 80° 

Now, 

⇒ 40<60<80⇒∠A< ∠B < ∠C 

⇒ ∠Cis greater angle and ∠A is smaller angle 

Now, ∠A<∠B<∠C 

⇒ BC<AAC<AB 

[∵Side opposite to greater angle is larger and side opposite to smaller angle is smaller] 

∴ AB is longest and BC is smallest or shortest side. 

 

 

 

shaalaa.com
  Is there an error in this question or solution?
Chapter 12: Congruent Triangles - Exercise 12.6 [Page 81]

APPEARS IN

R.D. Sharma Mathematics [English] Class 9
Chapter 12 Congruent Triangles
Exercise 12.6 | Q 1 | Page 81

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

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


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

  


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


ABC is a triangle in which ∠B = 2 ∠C. D is a point on BC such that AD bisects ∠BAC and AB = CD.
Prove that ∠BAC = 72°. 


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

The measure of each angle of an equilateral triangle is 60° 

 


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

In an equilateral triangle all angles are ..... 


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 


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

Sum of any two sides of a triangle is greater than twice the median drawn to the third side. 


If the angles of a triangle are in the ratio 2 : 1 : 3, then find the measure of smallest angle.


If the measures of angles of a triangle are in the ratio of 3 : 4 : 5, what is the measure of the smallest angle of the triangle?


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


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 = ______.


The angles of a right angled triangle are


D is a point on the side BC of a ∆ABC such that AD bisects ∠BAC. Then ______.


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


In ∆PQR, ∠P = 70° and ∠R = 30°. Which side of this triangle is the longest? Give reason for your answer.


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


In a triangle ABC, D is the mid-point of side AC such that BD = `1/2` AC. Show that ∠ABC is a right angle.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×