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Example 1 - Page 120 - Chapter 5 Class 7 - Parallel and Intersecting Lines (Ganita Prakash)
Last updated at July 24, 2025 by Teachoo
Class 7 (Ganita Prakash & Old NCERT)
Chapter 5 Class 7 - Parallel and Intersecting Lines (Ganita Prakash)
- Intersecting Lines
- Parallel and Perpendicular lines
- Between lines
- Parallel and Perpendicular lines in Paper Folding
- Figure it out - Page 113, 114
- Transversals
- Corresponding Angles
-
Alternate Angles
- Interior angle on Same side of Transversal
- Drawing Parallel Lines
- Parallel Illusions
- Figure it out - Page 123, 124, 125
Transcript
Example 1 - Page 120 In Fig. 5.26, parallel lines l and m are intersected by the transversal t. If ∠6 is 135°, what are the measures of the other angles? Since lines l &m are parallel, Corresponding angles are equal ∠ 2 = ∠ 6 ∠ 2 = 135° And, vertically opposite angles are equal ∠ 4 = ∠ 2 ∠ 4 = 135° Similarly, ∠ 6 & ∠ 8 are vertically opposite angles ∠ 8 = ∠ 6 ∠ 8 = 135° Now, on line l ∠ 1 & ∠ 2 are linear pair ∠ 1 + ∠ 2 = 180° ∠ 1 + 135°= 180° ∠ 1 = 180° – 135° ∠ 1 = 45° Now, ∠ 1 and ∠ 5 are corresponding angles, and they are eequal ∠ 5 = ∠ 1 ∠ 5 = 45° Since ∠ 1 & ∠ 3 are vertically opposite angles ∠ 3 = ∠ 1 ∠ 3 = 45° Also, Since ∠ 5 & ∠ 7 are vertically opposite angles ∠ 7 = ∠ 5 ∠73 = 45°
