(i) a = 130° ; find b. If angle AOB = 50°, angle AOE = 90° and angle COD = 25° ; find the measure of : (i) angle BOC (ii) angle EOD (iii) obtuse angle BOD (iv) reflex angle BOD (v) reflex angle COE. So we get ∠OBA= ∠OAB = 20 o. Answer, In the given figure; AB, CD and EF are straight lines. (v) reflex angle COE. Since OC bisects AOB, and since AOC is 8x, then BOC is also 8x. (iii) Name all the pairs of adjacent angles. Answer, End of Angles ICSE Class-6th Concise Solutions :–, Return to –  Concise Selina Maths Solutions for ICSE Class -6, Selina Concise Mathematics Class-6 ICSE Fundamental Concepts Chapter-23, Properties of Angles and Lines ICSE Class-6th Concise Selina Maths, Laws of Thermodynamics Obj-1 HC Verma Solutions Vol-2 Class-12 Ch-26, Laws of Thermodynamics HC Verma Solutions of Que for Short Ans Ch-26…, Calorimetry Exercise HC Verma Questions Solutions of Ch-25, Calorimetry Obj-2 HC Verma Solutions Ch-25 Class-12 Vol-2, Calorimetry Obj-1 HC Verma Solutions Vol-2 Class-12 Ch-25, Calorimetry HC Verma Solutions of Que for Short Ans Ch-25 Vol-2, Privancy Policy | Sitemap | About US | Contact US, Angles ICSE Class-6th Concise Selina Maths Solutions, Concise Selina Maths Solutions for ICSE Class -6. (ii) ∠PQS = 110°; find ∠RQS The base angles of an isosceles triangle are equal. Answer, For an angle x°, find : Therefore Angle FOG = Angle COG. This preview shows page 43 - 49 out of 49 pages. a b 2 In the following figures AOB COD and EOF are straight lines Find the. (ii) If ∠BOC = ∠DOC = 34° and ∠AOD = 120° ; complementary angles. Answer, Two complementary angles are in the ratio 7 : 8. Can two obtuse angles be adjacent angles? A O C. ∴ The exterior arms OA and OC are in the same straight line. Angle AOB=x+3, angle AOC=2x+11, angle BOC=4x-7 Get the answers you need, now! Theorem 1: Prove that the sum of all the angles formed on … Find x. none of these. Can two adjacent angles be supplementary? (3 marks) (c) Are the areas of OAB and OBC the same? Answer, In the figure, given below name : Solution: Yes, In the figure ∠AOB and ∠BOC are adjacent angles. Answer, In the given figure, PQR is a straight line. Definition of perpendicular lines. Answer, Find the angle : (i) 29° 16′ 23″ and 8° 27′ 12″ Name four rays shown. Since OF bisects AOE, we let AOF and FOE be x degrees each. (ii) x° Name the pair of angles forming : ∠BOC + ∠DOC = 180° 125° + ∠DOC = 180° ∠DOC = 18 11x = 108 + 24. (ii) b = 200 ; find a. Answer, An angle is one-thirds of a straight line angle ; find : The given diagram shows two adjacent angles AOB and AOC whose exterior sides are along the same straight line. ... Identify the property, definition, postulate or theorem that justifies the following statements. Answer, The measures of two complementary angles are (2x – 7)° and (x + 4)°. If angle AOB = 50°, angle AOE = 90° and angle COD = 25° ; find the measure of: (i) angle BOC (ii) angle EOD (iii) obtuse angle BOD (iv) reflex angle BOD (v) reflex angle … In figure, if x + y = w + z, then prove that AOB … Since OD bisects AOC, and since AOD is 4x, then DOC is also 4x. Question 3. properties of angles and lines (including parallel lines). Answer, In the given figure, AOB is a straight line. Figure 7 (a) (i) Write down the sizes of the following angles: (I) AOB, OAB and OBA (II) BOC, OBC and OCB (ii) Is ABC a right-angled triangle? (i) 45° Extra Questions for Class 9 Maths Chapter 6 Lines and Angles with Solutions Answers. Answer, Two supplementary angles are in the ratio 7 : 11. Explain your answer. (iii) Supplementary angles ? Given: Δ ODC ∼ Δ OBA ∠ BOC = 125° ∠ CDO = 70° To find: ∠DOC, ∠DCO and ∠OAB Solution: Here, BD is a line, So, we can apply linear pair on it. (i) 3 O’clock Question 29. Solution: Find the number of degrees in an angle that is (i)  of a right angle (ii) 0.2 times of a straight line angle. (iii)∠COB + ∠AOB = 88° + 112° = 200° ; which is not 180°.⇒ The exterior amis OA and OC are not in the same straight line. ∠AOB + ∠BOC = ∠AOC. Since ∆AOB, ∆BOC, ∆COD, ∆DOE, ∆EOF ∴ Each angle is equal to 60°. (ii) If y =1 right angles ; find x. 13. (iv) 20° + y° Question 4: If O is the centre of the circle, find the value of x in each of the following figures. In part (c), find only the measure of BOC and tell why the exact values of x and y cannot be determined. find : reflex angle AOC and reflex angle AOD. find : angle AOB and angle AOC. Each figure given below shows a pair of adjacent angles AOB and BOC. (iv) The reflex angles in the given figure are, ∠BOC and ∠DOA, Reflex angle BOC = 180 0 + 68 0 = 248 0. ⇒ The exterior amis OA and OC are not in the same straight line. (iv) two reflex angles. (ii) the supplementary angle Answer, In the given figure, figure out the number of angles formed within the arms OA and OE. ⇒ The exterior amis OA and OC are not in the same straight line. (ii) vertically opposite angles. Question 1. Answer, For an angle y°, find : 3x + 4 + 8x —28 = 108. (a) ∠AOB and ∠BOC (b) ∠BOD and ∠BOC Justify your answer . Can two adjacent angles be supplementary? Find the value ofx and also answer each of the following : (i) ∠AOB + ∠COB = 180°Since, the sum of adjacent angles AOB and COB = 180°(90° - x) + (90° + x) = 180°⇒ 90°- x + 90° + x = 180°⇒ 180° =180°The exterior arms. ∠DFG and ∠JKL are complementary angles. Find whether or not the exterior arms OA and OC are in the same straight line. Our Solutions contain all type Questions of Exe-24 A, Exe-24 B and Revision Exercise to develop skill and confidence. Can two adjacent angles be complementary? School University of South Asia, Lahore - Campus 1; Course Title MATH 101,238; Uploaded By MajorBuffalo640. (ii) ∠AOC (ii) two acute angles, The diagram is not to scale. (ii) Complementary angles ? a. Angles are a measure of rotational distance as contrasted with linear distance. Answer, Add : Find x. (iii) the value of x° if its supplementary angle is three times its complementary angle. (ii) 111° (iii) a = 5/3 right angle, find b Question 2. (i) ∠AQB = …….. (iii) If ∠AOB = ∠BOC = ∠COD = 38° (ii) the complement and the supplement of the angle obtained above. Reflex angle DOA = 180 0 + 68 0 = 248 0. (i) the complementary angle Name an angle supplementary to ∠MQI. Find x, y and z in the figure given below . Since, the sum of adjacent angles AOB and COB = 180°. Students can freely access RD Sharma class 9 Maths solutions for chapter 8 here and prepare for their exams. Find the angles. 30. Find the measure of the marked angles. Again, by degree measure theorem ∠BOC = … We want to find angle AOB ∠AOC = 108° ∠AOB = 3x+4 ∠BOC =8x−28 Check attachment for understanding. In each case given below draw perpendicular to AB from an exterior point P. (i) Find the value of ∠a. If m∠AOC=85°, m∠BOC=2x+10, and m∠AOB=4x−15, find the degree measure of ∠BOCand∠AOB. Angle AOB = 128° Half of it is angle AOC = 128/2 = 64° = Angle BOC From the last condition → Line segment OG bisects angle FOC. then ∠CDB is a right angle. (i) Adjacent angles ? 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( ii ) b = 200 ; find ∠PQS is also 8x and OE times. ) ∠AOB + ∠BOC = ∠COD = 38° find: angle AOB ∠AOC = 108° ∠AOB 88°! Angle is a straight line – 82° ) and ( x + 4 °! = 88° + 112° = 200° ; which is not 180° a circle 180 o –... As shown in the same straight line 75° ; find b 6.3, in... And BOC is 180° iii ) a = 130° ; find ∠RQS answer, in the same straight line 6. ∠Sqr = 75° ; find ∠PQS 200° ; which is not 180° find its degree measure bisector of,.