A 4-sided polygon is a quadrilateral
Polygon
Polygon is a simple closed figure made of line segments
A quadrilateral has
- 4 vertices − A, B, C, D
- 4 sides − AB, BC, CD, DA
- 4 angles − ∠A, ∠B, ∠C, ∠D
Opposite sides
- AB & CD are opposite sides
-
AD & BC are opposite sides
Adjacent sides
- AB, BC are adjacent sides
- AB, AD are adjacent sides
- BC, CD are adjacent sides
-
CD, DA are adjacent sides"
Opposite angles
- ∠A, ∠C are opposite angles
- ∠B, ∠D are opposite angles
Adjacent angles
- ∠A, ∠B are adjacent angles.
- ∠A, ∠D are adjacent angles.
- ∠B, ∠C are adjacent angles.
- ∠C, ∠D are adjacent angles.
Diagonals of a quadrilateral
Line joining two opposite vertices of a quadrilateral is a diagonal.
Here, AC, BD are diagonals of the quadrilateral.
And they meet at point O.
