Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Definition of a Polygon: A closed 2D shape with straight sides.
Naming Polygons: Triangles (3 sides), Quadrilaterals (4 sides), Pentagons (5 sides), Hexagons (6 sides), Octagons (8 sides).
Regular vs. Irregular: Regular polygons have all sides and angles equal; irregular polygons do not.
Vertices: The 'corners' where two sides meet.
Properties of Quadrilaterals: Squares have 4 equal sides and 4 right angles; Rectangles have opposite sides equal and 4 right angles.
Circle Parts: The center (middle point), radius (center to edge), and diameter (line through center from edge to edge).
Parallel Lines: Lines that stay the same distance apart and never meet.
Perpendicular Lines: Lines that meet at a right angle (90°).
📐Formulae
Perimeter of a polygon =
Number of vertices =
💡Examples
Problem 1:
A shape has 6 straight sides of equal length. What is the name of this shape, and is it regular or irregular?
Solution:
Regular Hexagon
Explanation:
A six-sided polygon is called a hexagon. Because all sides are mentioned as being equal in length, it is classified as 'regular'.
Problem 2:
If the radius of a circle is , what is the length of its diameter?
Solution:
Explanation:
The diameter of a circle is always twice the length of the radius. So, .
Problem 3:
A rectangle has two sides that are long and two sides that are long. Calculate the perimeter.
Solution:
Explanation:
The perimeter is the total distance around the shape. .