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Assertion and Reason Questions for Class 9 Maths Chapter 7 Triangles, , Directions: In the following questions, a statement of assertion (A) is followed by a, statement of reason (R). Mark the correct choice as:, , (a) Both assertion (A) and reason (R) are true and reason (R) is the correct explanatic, of assertion (A)., , (b) Both assertion (A) and reason (R) are true but reason (R) is not the correct, explanation of assertion (A)., , (C) Assertion (A) is true but reason (R) is false., , (d) Assertion (A) is false but reason (R) is true., , Q.1. Assertion : In the adjoining figure, X and Y are respectively two points on equal, sides AB and AC of AABC such that AX = AY then CX = BY., Reason: If two sides and the included angle of one triangle are equal to two sides anc, , the included angle of the other triangle, then the two triangles are congruent, , Answer, , Answer: (a), , Q.2. Assertion : In the given figure, BO and CO are the bisectors of 2B and ZC, respectively. If 7A = 50° then “BOC = 115°, , Reason: The sum of all the interior angles of a triangle is 180°
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VN, , B c, , Answer, , Answer: (a), , Q.3. Assertion: Two angles measures a - 60° and 123° - 2a. If each one is opposite to, equal sides of an isosceles triangle, then the value of a is 61°., , Reason: Sides opposite to equal angles of a triangle are equal., , Answer, , Answer: (b), , Q.4. Assertion : In AABC, 2C = ZA, BC = 4 cmand AC =5 cm. Then, AB=4 cm, , Reason: In a triangle, angles opposite to two equal sides are equal., , Answer, , Answer: (b), , Q.5. Assertion : In AABC, BC = AB and B = 80°. Then, 7A = 50°, , Reason: In a triangle, angles opposite to two equal sides are equal, , Answer, , Answer: (a)
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Q.6. Assertion : In AABC, D is the midpoint of BC. If DL1 AB and DM I AC such that DL =, DM, then BL = CM, , Reason: If two angles and the included side of one triangle are equal to two angles, , Answer, , Answer: (b), , Q.7. Assertion : Angles opposite to equal sides of a triangle are not equal., , Reason : Sides opposite to equal angles of a triangle are equal., , Answer, , Answer: (d), , Q.8. Assertion : In AABC, AB = AC and 7B = 50°, then 4C is 50°., , Reason: Angles opposite to equal sides of a triangle are equal., , Answer, , Answer: (a)
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Q.9. Assertion : AABC and ADBC are two isosceles triangles on the same base BC and, vertices A and D are on the same side of BC. If AD is extended to intersect BC at E, then, AABD = AACD, , Reason: If in two right triangles, hypotenuse and one side of a triangle are equal to the, , hypotenuse and one side of other triangle, then the two triangles are congruent., , Answer, , Answer: (b), , Q.10. Assertion : In triangles ABC and PQR, ZA= ZP, ZC = “Rand AC = PR. The two, triangles are congruent by ASA congruence., Reason: If two angles and the included side of one triangle are equal to two angles and, , the included side of the other triangle, then the two triangles are congruent., , Answer, , Answer: (a), , Q.11. Assertion : In AABC and APQR, AB = PQ, AC = PR and BAC = ZQPR then AABC, = APaR, , Reason: Both the triangles are congruent by SSS congruence., , A Pp, , B c Q R
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Answer, , Answer: (c), , Q.12. Assertion: In the given figure, BE and CF are two equal altitudes of AABC then, AABE = AACF, , Reason: If two angles and one side of one triangle are equal to two angles and the, , corresponding side of the other triangle, then the two triangles are congruent., , Answer, , Answer: (a), , Q.13. Assertion: In ABC, 7A = ZC and BC = 4 cmand AC = 3 cm then the length of side, AB=3 cm,, , Reason: Sides opposite to equal angles of a triangle are equal., , Answer, , Answer: (d)
