Geometry | Term 1 Chapter 4 | 6th Maths - Summary
6th Maths : Term 1 Unit 4 : Geometry
A line extends along both directions without end.
A line segment has two end points.
Parallel lines never meet.
When two lines meet they are called intersecting lines.
When two rays have common starting point, they form an angle at that point.
We measure angles using protractor.
An angle whose measure is less than 90º is called an acute angle.
An angle whose measure is exactly 90º is called a right angle.
An angle whose measure is greater than 90º is called an obtuse angle.
When the two rays or lines coincide, they are said to make angle zero, that is 0º.
Two angles are complementary when they add up to 90º.
Two angles are supplementary when they add up to 180º.
Given any two points there is a unique line passing through them.
When three points lie on a line, they are said to be collinear.
When two lines meet each other at 90°s at the point of intersection, they are called perpendicular lines.
When three or more lines pass through the same point, they are said to be concurrent. That point is called the Point of Concurrency.