1. By Krishna Kumar Sahu TGT - MATHS Kendriya Vidyalaya NO. 2 CPE ITARSI

2. How many types of angles ?. Vertically Opposite Angles. Vertically Opposite Angles. Alternate interior Angles. Alternate interior Angles. Alternate Exterior Angles. Alternate Exterior Angles. Corresponding Angles. Corresponding Angles. Linear pair of angles. Linear pair of angles. Interior Angles on the same side of a Transversal. Interior Angles on the same side of a Transversal. End Show. End Show.

3. VERTICALLY OPPOSITE ANGLES l m 1 2 3 4 5 6 7 8 Here l & m are two lines, t is transversal Then t 1, 3 2, 4 5, 7 6, 8 Vertically Opposite Angles If two lines are intersecting each other then vertically opposite angles are always equal. So 1 =3,2 =4,5 =7,6 =8

4. Alternate Interior Angles Here l & m are two lines, t is a transversal then 1, 4 2, 3 Alternate Interior Angles 1 2 3 4 l m t If two lines are parallel to each other then alternate interior angles are equal 1 =4,2 =3 12 34

5. CORRESPONDING ANGLES Here l & m are two lines, t is transversal Then 1, 3 2, 4 5, 7 6, 8 Corresponding Angles If two lines are parallel to each other then corresponding angles are always equal. So 1 =3,2 =4,5 =7,6 =8 1 2 34 l m t 1 2 34 5 7 6 8 7 8 5 6

6. CORRESPONDING ANGLES Alternate Exterior Angles. Here l & m are two lines, t is a transversal then 1, 4 2, 3 Alternate exterior Angles 1 2 3 4 l m t If two lines are parallel to each other then alternate exterior angles are equal 1 =4,2 =3 1 2 3 4

7. Interior angles on the same side of a transversal Here l & m are two lines, t is a transversal then 2, 4 1, 3 Pair of interior angles on the same side of transversal 1 2 3 4 l m t If two lines are parallel to each other then sum of interior angles on the same side of transversal is 180. 2 +4 = 180 & 1 +3 = 180 12 34

8. Linear pair of angles Angles on a straight line is Linear pair of angles & their sum is always equal to 180 o. ABC AB C D ACB = 180 0 ABD +DBC = 180 0 Two adjacent angles form a linear pair. Two acute angles not form a linear pair. Two obtuse angle not form a linear pair. One obtuse and one acute angle form a linear pair. Two right angles form a linear pair.