📏 What are Lines?

A line is a straight path that extends endlessly in both directions. It has no endpoints.
Line segment: A part of a line with two endpoints.
Ray: A line that starts at one point and goes on forever in one direction.

• Line: ↔️ AB (both sides go on forever)
• Line Segment: — AB (fixed length)
• Ray: → AB (starts at A, goes through B and beyond)

📐 What are Angles?

An angle is formed when two rays start from the same point. This point is called the vertex, and the rays are called arms of the angle.

Example: ∠ABC where B is the vertex and BA, BC are the arms.

🧭 Types of Angles

• Acute Angle: Less than 90°
• Right Angle: Exactly 90° (like a corner)
• Obtuse Angle: More than 90° but less than 180°
• Straight Angle: Exactly 180°
• Reflex Angle: More than 180°
• Complete Angle: Exactly 360°

📏 Intersecting, Parallel and Perpendicular Lines

• Intersecting lines: Lines that cross each other at one point
• Parallel lines: Lines that never meet, even if extended
• Perpendicular lines: Lines that meet at a 90° angle

🔄 Pairs of Angles

• Complementary Angles: Two angles that add up to 90°
• Supplementary Angles: Two angles that add up to 180°
• Adjacent Angles: Angles that share a common arm and vertex
• Vertically Opposite Angles: Equal angles formed when two lines intersect

📚 Real Life Use of Lines and Angles

• Corners of rooms and books (right angles)
• Clock hands (angles between them)
• Road intersections (perpendicular, intersecting)
• Ladders leaning on walls (forming angles)

📝 Activities in Ganit Prakash

• Using matchsticks to form angles and shapes
• Drawing angles using protractor
• Finding angles in objects around you

🌟 Summary

Lines and angles are the building blocks of geometry. Understanding their types and properties helps us with construction, drawing, architecture, and even art!

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