This pdf contains:- Scalene Triangle Isosceles Triangle Equilateral Triangle Triangles Based on Angle: Acute, Right, and Obtuse Angled Triangle Median, Altitude, Angle Bisector, Perpendicular Bisector
1. Class 8: Chapter 30 – Triangles (Lecture Notes I) Triangle: We just studied polygons. Triangle is a polygon with three sides. So, we could define a triangle as a plane closed figure bounded by three line segments. A triangle is a polygon with three edges and three vertices. It is one of the most basic shapes in geometry. A triangle with vertices A, B, and C is denoted by ∆ABC. Kinds of Triangles 1. This is a classification of triangles based on the length of the sides Scalene Triangle A triangle in which all three sides are of different lengths is called Scalene Triangle. In this type of triangle: ∠A ≠ ∠B ≠ ∠C Isosceles Triangle A triangle in which two sides are of the same length is called Isosceles Triangle In this type of triangle: ∠B = ∠C 1 For more information please go to: https://icsemath.com/
2. Equilateral A triangle in which all three sides are Triangle of the same length is called Equilateral Triangle. In this type of triangle: ∠A = ∠B = ∠C Some of the diagrams have been adopted from https://en.wikipedia.org/wiki/Triangle 2. Classification of Triangles based on the angles Acute-angled A triangle in which all the three angles Triangle are more than 0° and less than 90° is called acute-angled triangle. Right-angles A triangle in which one of the angles is Triangle 90° is called right-angled triangle. Obtuse-angled A triangle in which one of the angles is triangle more than 90° but less than 180° is called obtuse-angled triangle. Some of the diagrams have been adopted from https://en.wikipedia.org/wiki/Triangle Terms related to a Triangle 2 For more information please go to: https://icsemath.com/
3. Median A line segment joining the vertex to the mid-point of the opposite side of a triangle is called median. In this vertex A is meeting at point D (such that BD=DC) midpoint of BC Centroid The point of intersection of three medians is called centroid. Altitude The perpendicular drawn from the vertex to the opposite side. Here AD is the altitude of the triangle AD and BC is the base. Orthocenter The intersection of the three altitudes is called the Orthocenter of the triangle. Here A is the Orthocenter of the triangle. 3 For more information please go to: https://icsemath.com/
4. Angle Bisector A line segment that bisects and interior angle of a triangle is called angle bisector. Here AD is bisecting ∠BAC into two equal ∠BAD and ∠DAC Incentre and The point of intersection of Incircle internal angle bisectors is called the Incentre. I is the Incentre of the triangle. Now if you draw a circle with the center I in such a way that it touches all the three sides of the triangle, then that is called Incircle. Perpendicular A line bisecting any side of the Bisector or Right triangle and perpendicular to Bisector it is called perpendicular bisector of that side of the triangle. Here BC is being bisected by DE. BD=DC and ED ⊥ BC. 4 For more information please go to: https://icsemath.com/
5. Circumcenter The point of intersection of the and Circumcircle perpendicular bisectors of the sides of the triangle is called Circumcenter. Here O is the circumcenter. Exterior Angle ∠ACD is the exterior angle and and Interior ∠CBA and ∠ BAC are opposite Opposite Angles interior angles of this exterior of a Triangle angle. Some of the diagrams have been adopted from https://en.wikipedia.org/wiki/Triangle 5 For more information please go to: https://icsemath.com/
+1-315-636-4485
+91 98151-74050 
