PARALLEL LINES

PARALLEL LINES

Those line which never intersect each other and lie in the same plane are called parallel lines.

If a transversal intersects two parallel lines then

·     Each pair of corresponding angle is equal.

·     Each pair of alternate angle is equal.

·     The sum of the interior angles on the same side of the transversal is equal to 180 degree.

·     Two corresponding angles are equal so two straight lines are parallel.

·     Two alternate angles are equal so  the two straight lines are parallel.

·     Two interior angle on the same side of the transversal and their sum is 180 degree so the two straight line are parallel

                     Two parallel lines are always equidistant from one another.

                     Those line which are in the same plane and are parallel to the same line , are parallel to one another .

                     Two intersecting straight lines can’t be both parallel to a third straight line.

                     Those straight lines which are perpendicular to the same straight line are parallel to each other.

                     Two parallel lines make equal intercepts on those all transversals , which are perpendicular to the given parallel lines .

                     The straight line drawn through the middle point of a side of a triangle parallel to another side of the triangle bisects the third side.

                     The straight line which joints the middle points of two sides of a triangle is parallel to the third side .

                     If three parallel lines cut equal intercepts on a transversal ,They will also cut equal intercepts on other transversal.

                     If a straight line parallel to one side of the triangles cut two other sides of the triangle at different points , then the intercepts made on these lines are proportional to those sides .

      Three parallel lines make such intercepts on two transversals which are proportional to one another i.e; the ratio of the intercepts on one transversal is equal to the ratio of intercepts on second transversal.