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Class 7 - Mathematics - Unit 5: Lines And Angles - Problems and SolutionsQuestion 105
Class 7 - Mathematics - Unit 5: Lines And Angles - Problems and Solutions
Question. 105
105. In Fig. 5.58, PQ, RS and UT are parallel lines.
(i) If c = 57° and a = c/3, find the value of d.
(ii) If c = 75° and a = (2/5)c, find b.
Answer:
(i) d = 142°
(ii) b = 45°
Detailed Answer with Explanation:
(i) Using parallel line properties, d = 180° − (c + a). Substituting values gives 142°.
(ii) From c = 75° and a = (2/5)c = 30°, corresponding angle properties give b = 45°.