Properties of lines

In this session we are going to learn about Properties of lines To study about the  properties of lines and angles we first talk about line as the group of endless points which are collinear and extends endlessly in both the directions. The lines do not have any fixed length and has arrows at both the ends, which indicates that the line is extending in both sides.
Here are some of the properties of the lines and angles:
If we have a pair of lines which intersect each other at only one point, then we say that the lines are intersecting at a point. If the two lines are intersecting then the pair of opposite angles so formed are called  vertical opposite angles. We must remember that the pair of  vertical opposite angles are  equal. Another pair of  lines we talk about are  parallel lines, the pair of lines are called parallel, when we find that the pair of lines  do not meet at all , or it is said intersecting lines  at infinite which we cannot  see at all.  Thus we say that the lines are parallel then the  perpendicular distance between  the two lines at all the points are equal. (know more about cbse sample papers, here)

Next type of lines are called coinciding  lines, when we have two lines on the plane, such that its all points are coinciding so that when the lines are plotted, the two lines overlap each other. Two lines are called perpendicular to each other, when we find that the pair of lines form an angle of 90 degrees  between each other, then the  lines are called perpendicular to each other. Remember that the line segment is the part of the line which has a fixed length and  so it has two end points. In the next session we will discuss about Geometric concepts.