Point line line segment ray and plane :
In this section, we are going to see "Point line line segment ray and plane"
Point is not something new to us. Many graphs are being drawn using points.
A point is smaller than a tip of a pencil or pen used by us. Therefore a point has not length, width, height or thickness.
A point indicates a definite position.
Points are usually denoted by capital letters A, B, C and so on as given below.
Observe the figure given below carefully.
As the space in between the points decreases they join to form a line. A line is a set of points closely arranged without gap.
Mark A, B on a sheet of paper using a scale and draw a line passing through these points.
This is a straight line.
It is represented as straight line AB or line "l".
When we represent a straight line as AB, it means,
(i) The line passes through the points A and B.
(ii) The line extends on either side of A and B.
Observe the names given for the following straight lines.
A ray starts from a fixed point and extends indefinitely in other direction.
1. Starting point of the ray is A.
2. The ray passes through the points A and B.
3. The ray extends through the point B.
A ray is a straight line with a starting point and extends indefinitely in one direction.
If a sheet of paper is folded and then opened, the folded part represents the line segment.
It is shown in the figure given below.
Mark X, Y and Z on the straight line AB.
Consider AX a part of the straight line, which starts at A and ends at X. So, it has a particular length. This is called a line segment. It can be denoted as line segment AX.
Few more line segments from the above figure are AY, AB, XY, XB, YB, XZ.
Therefore line segment is a part of a line. It has a starting point and end point.
A line segment has definite length.
Straight lines, points and rays can be represented in a sheet of paper or on the black board. Isn't it ?
Likewise floor, wall, black board, card board and top portion of the table are few examples of plane.
A plane is a flat surface which extends indefinitely in all directions as given in the figure given below.
How many points are required to form a plane ?
It is enough to have three points that do not lie on the same straight line.
Collinear points :
1. Draw the straight lines passing through the points A and B.
2. Check whether you can draw a straight line passing through the points A, B and C.
3. Draw a straight line passing through the points P, Q and R.
1. You can draw a straight line passing through the two points A and B.
2. Since A, B and C are on the same straight line, a straight line can not be drawn through A, B and C.
3. A straight line can be drawn through P, Q and R, as they lie on the same straight line.
So, P, Q and R are collinear points.
Hence, the following statements are true.
(i) A straight line can be drawn through any two given points.
(ii) It is not always possible to draw a straight line passing through any 3 points.
(iii) But a straight line can be drawn passing through 3 collinear points.
After having gone through the stuff given above, we hope that the students would have understood "Point line line segment ray and plane".
Apart from the stuff given above, if you want to know more about "point line line segment ray and plane", please click here
Apart from the stuff "Point line line segment ray and plane" given in this section, if you need any other stuff in math, please use our google custom search here.
APTITUDE TESTS ONLINE
ACT MATH ONLINE TEST
TRANSFORMATIONS OF FUNCTIONS
ORDER OF OPERATIONS
MATH FOR KIDS
HCF and LCM word problems
Word problems on quadratic equations
Word problems on comparing rates
Converting repeating decimals in to fractions