Page 93 - Revised Maths Wisdom Class - 6

Lines and Angles 91

Plane

A plane is a flat surface that extends indefinitely in all directions. It is a two-dimensional concept which has no
height or thickness. For example, surface of a white board, table top, etc.

P S

• A • B

X • C
Q R
Plane PQRS Plane X Plane ABC
A plane can be represented either by a rectangle or a parallelogram in three different ways as shown in figure.

Point P
A point is a mark of position or location on a plane. It has no length, no breadth and no height, A
i.e., it is zero dimensional. For example, the tip of a toothpick, needle or pencil. B
A point is represented by a capital letter of English Alphabet. In the figure P, A, B, Q and C all
represent points and are read as point P, point A and so on. Q C
Points
Line B

A line is a straight path that extends indefinitely in both directions. It has no end points. It has
no definite length and is one-dimensional. For example, a crease in a paper, a stretched string.
Remember a line has no thickness. A
A line is represented as AB or line l as shown in figure.
l
Line Segment Lines

A line segment is a part of a line. It has two end points and we can measure its length. It is also B
one dimensional. For example, edge of a ruler.
A
A line segment is represented as AB as shown in figure. Line segment

Ray Y

A ray is a part of line. It begins from one point and extends indefinitely only in one direction.
For example, sun rays, beam of torch, etc. A ray is represented as XY as shown in figure. X Ray

Line Line Segment Ray

1. It has no end points 1. It has two end points 1. It has one end point.
2. It does not have a definite length. 2. It has a definite length that can be 2. It does not have a definite length.

3. It cannot be drawn on a sheet but measured. 3. It cannot be drawn on a sheet but is
is represented by a figure. 3. It can be drawn on a sheet. represented by a figure.
4. 4.
P Q 4. A B O X

Here, PQ represents a line. Here, AB represents a line segment. Here, OXrepresents a ray.