English

Suppose the Angles of a Triangle Are (A − D), a , (A + D) Such that , (A + D) >A > (A − D). - Mathematics

Advertisements
Advertisements

Question

Suppose the angles of a triangle are (a − d), a , (a + d) such that , (a + d)  >a >  (a − d).

Answer in Brief
Advertisements

Solution

\[a - d + a + a + d = 180 \left[ angle sum property \right]\]
\[ \Rightarrow 3a = 180\]
\[ \Rightarrow a = 60\]
\[Now, \left( a + d \right) = 2\left( a - d \right)\]
\[ \Rightarrow a + d = 2a - 2d\]
\[ \Rightarrow a = 3d\]
\[ \Rightarrow d = \frac{60}{3} = 20\]
\[\text{ Therefore, the three angles of a triangle are 40, 60, 80 }  .\]

shaalaa.com
  Is there an error in this question or solution?
Chapter 5: Arithmetic Progression - Exercise 5.5 [Page 30]

APPEARS IN

RD Sharma Mathematics [English] Class 10
Chapter 5 Arithmetic Progression
Exercise 5.5 | Q 11 | Page 30

RELATED QUESTIONS

Find the sum of first 30 terms of an A.P. whose second term is 2 and seventh term is 22


In an AP given a = 8, an = 62, Sn = 210, find n and d.


A spiral is made up of successive semicircles, with centres alternately at A and B, starting with centre at A of radii 0.5, 1.0 cm, 1.5 cm, 2.0 cm, .... as shown in figure. What is the total length of such a spiral made up of thirteen consecutive semicircles? (Take `pi = 22/7`)

[Hint: Length of successive semicircles is l1, l2, l3, l4, ... with centres at A, B, A, B, ...  respectively.]


The sum of three terms of an A.P. is 21 and the product of the first and the third terms exceed the second term by 6, find three terms.


A sum of ₹2800 is to be used to award four prizes. If each prize after the first is ₹200 less than the preceding prize, find the value of each of the prizes


The angles of quadrilateral are in whose AP common difference is 10° . Find the angles.


Kargil’s temperature was recorded in a week from Monday to Saturday. All readings were in A.P. The sum of temperatures of Monday and Saturday was 5°C more than sum of temperatures of Tuesday and Saturday. If temperature of Wednesday was –30° celsius then find the temperature on the other five days.


The 9th term of an A.P. is equal to 6 times its second term. If its 5th term is 22, find the A.P.


For what value of p are 2p + 1, 13, 5p − 3 are three consecutive terms of an A.P.?

 

Write the nth term of the \[A . P . \frac{1}{m}, \frac{1 + m}{m}, \frac{1 + 2m}{m}, . . . .\]

 

Let Sn denote the sum of n terms of an A.P. whose first term is a. If the common difference d is given by Sn − kSn−1 + Sn−2, then k =


If S1 is the sum of an arithmetic progression of 'n' odd number of terms and S2 the sum of the terms of the series in odd places, then \[\frac{S_1}{S_2} =\]

 


Q.3 

 


Q.18


If the sum of the first m terms of an AP is n and the sum of its n terms is m, then the sum of its (m + n) terms will be ______.


The famous mathematician associated with finding the sum of the first 100 natural numbers is ______.


Find the sum:

`4 - 1/n + 4 - 2/n + 4 - 3/n + ...` upto n terms


Find the sum of all even numbers from 1 to 250.


The sum of A.P. 4, 7, 10, 13, ........ upto 20 terms is ______.


The sum of 40 terms of the A.P. 7 + 10 + 13 + 16 + .......... is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×