Geometry: 2D Shapes & Angles

Geometry: 2D shapes and angles involves understanding the properties of flat shapes and how angles work. This knowledge helps you solve problems involving shape identification, perimeter, area, and angle calculations.

🔹 2D shapes (two-dimensional shapes) are flat shapes with length and width but no thickness.

Common 2D shapes and their properties:

• Triangle – 3 sides; internal angles always add up to 180°.
• Quadrilateral – 4 sides; internal angles always add up to 360°.
• Square – 4 equal sides and 4 right angles (90°).
• Rectangle – 2 pairs of equal parallel sides and 4 right angles.
• Circle – A perfectly round shape where every point on the edge is the same distance from the centre.

📐 Angles measure the amount of turn between two lines that meet at a point (vertex). Angles are measured in degrees (°).

Types of angles:

[Image of different types of angles: acute, right, obtuse, straight, and reflex]

• Acute – Less than 90°
• Right angle – Exactly 90° (marked with a square corner)
• Obtuse – Greater than 90° but less than 180°
• Straight angle – Exactly 180° (a straight line)
• Reflex – Greater than 180° but less than 360°

✅ Knowing the properties of 2D shapes and how to work with angles is essential for solving geometry questions confidently.