Quadrilaterals

QUADRILATERALS

In Basic Technology, a quadrilateral is any four-sided figure used in drawing, design, and construction. It is very important in technical drawing, building, and fabrication work.

A quadrilateral is a closed shape with:

4 sides

4 angles

4 corners (vertices)

👉 The total sum of its interior angles is:

A + B + C + D = 360°

Types of Quadrilaterals

They include:

Square
All sides are equal

All angles are 90°

Used in tiles, frames, and plates

Rectangle

Opposite sides are equal

All angles are 90°

Used in doors, windows, books

Parallelogram
Opposite sides are parallel and equal

Opposite angles are equal

Used in structural designs

Rhombus
All sides are equal

Angles are not necessarily 90°

Used in design patterns

Trapezium (Trapezoid)

One pair of opposite sides is parallel

Used in bridge supports and roofing

Kite

Two pairs of adjacent equal sides

Used in craft and design

Importance in Basic Technology

Quadrilaterals are used in:

Technical drawing (shapes and projections)

Building construction (walls, windows, doors)

Woodwork and metalwork (frames, joints)

Engineering designs

Simple Example

A classroom door is a rectangle, while a floor tile may be a square.