Basic Geometry

Point

A point has no length or breadth. It is an exact location in space.

Line

A line has no end point. It is of infinite length we cannot draw a line on paper but it represent by a diagram.

Line sagment

A line sagment has two end point. It has a fixed length.

Ray

A Ray has one fixed starting point but no end point.

Plane

A plane is concept which can only be visualized by any level surface like table top, floor of room etc. All these surface have edge wheres a plane stretches endlessly on all sides like a line.

Curved Line

Curves are everything which you draw without lifting the pencil from the paper.

Angle

A figure consisting of two rays with common initial point is called an angle.

Acute Angle

Those Angles which are less than 90° is called Acute Angles (like: 1°,15°,25°,60°,80°...89°)

Right Angle

Angle of 90° is called Right Angle.

Obtuse Angle

Angle greater than 90° & less than 180° is called Obtuse Angle. (like: 95°,120°,...179°)

Straight Angle

Angle of 180° is called Straight Angle.

Reflex Angle

Angle which is greater than 180° and less than 360° is known as reflex angle(like:181°,....359°)

Relation b/w two Angles

Complementary Angles

If the sum of two angels is equal to 90° which are called Complementary Angles.

Eg. 35°&55° , 45°&45°, 60°&30°, etc.

Supplementary Angles

If sum of two angles is equal to the 180° which are called Supplementary Angles.

Eg. 120°&60°, 160°&20°, etc.

Vertically opposite angles

When two lines intersect each other then angles formed are known as vertically opposite angles.
vertically opposite angles are equal.

Parallel lines

Lines which do not intersect Each Other are known as parallel lines. Distance between two Parallel Lines always remains constant. Denoted by AB||CD.

Transverse line

A line which cuts any two or more than two lines if a transversal line cuts two Parallel Lines, then

Alternate angles are equal

Interior Angles

Exterior Angles

Corresponding angles are equal

2-Diamention

2D/plane figure, i.e. it have only length & breath.

Triangles & quadrilateral are some examples of plane figures.

Triangle

Which is surrounded by three sides is called a triangle. There are three sides & three angles in a Triangle.
Sum of three angles of a triangle is,

Sum of any two angles is greater than third angle.
Types of Triangle:-

On the Basis of sides

I) Equilateral triangle :- A triangle having all sides are equal.

AB = BC = CA

II) Isosceles triangle :- A triangle having only two sides are equal.

AC = CB

III) Scalene triangle :- A Triangle having no equal sides.

AB ≠ BC ≠ CA

On the Basis of Angles

I) Right Angle Triangle :- A Triangle in which one angle is 90°.

II) Acute Angle Triangle :- A Triangle in which all angle less than 90°.

III) Obtuse Angle Triangle :- A Triangle in which only one angle is greater than 90°.

Quadrilateral

It is surrounded by four sides is called quadrilateral.
Any four sides closed figure is called Quadrilateral.
The sum of the angles of a quadrilateral is 360°.

Rectangle

A four sides closed figure whose opposite sides are equal.
Each angle 90°(Right Angle)

Square

A four sides closed figure whose all sides are equal.
Each angle 90°(Right Angle)

Parallelogram

Parallelogram have both pair of opposite sides are parallel.
All sides not equal.
Any angle ≠ 90°.

Rhombus

A parallelogram in which all sides are equal.
Any angle ≠ 90°

Trapezium

A quadrilateral, in which only one pair of opposite side is parallel.

Circle

A closed figure in a plane which shows the path traced by moving about a point from a fixed point is called circle.
Fixed point is called Centre of circle.

Radius

The straight line joining the centre and circle is called radius.

Diameter

Straight line which passes through the centre and joining the circumference from both sides.

Circumference

The distance measured along a circle is called its circumference.

Maths (Basic Geometry)