1. Angles
•Definition: An angle is formed when two lines meet at a point (called the vertex).
•Types of Angles:
•Acute Angle: Less than 90° (sharp angle).
•Right Angle: Exactly 90° (like a corner).
•Obtuse Angle: Greater than 90° but less than 180° (wide angle).
•Straight Angle: Exactly 180° (a straight line).
Example:
If two lines meet and form a 90° angle, that’s a right angle.
2. Triangle Properties
• Types of Triangles:
• Equilateral Triangle: All sides and angles are equal (each angle is 60°).
• Isosceles Triangle: Two sides are equal, and two angles are equal.
• Scalene Triangle: No sides or angles are equal.
• Right-Angled Triangle: One angle is 90°.
Example:
A triangle with sides of 3 cm, 3 cm, and 4 cm is isosceles because two sides are the same.
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