90 Vertical Horizontal Oblique line a b Angles a + b = 180 o Angles at a Point b = 115 o Angle a = 180 – 115 = 65 o

Angles at a Point 90 Vertical Horizontal 360 o

Angles at a Point a b c d Angles at a point add to 360 o Angle a + b + c + d = 360 0

75 o 85 o 80 o a Example 1: Find angle a. Angles at a Point o Angle a = ( ) = = 120 o

Angle x = ( ) = = 65 o o 100 o x Example 2: Find angle x. Angles at a Point o

360 o in a circle. What does it mean? o 180 o 270 o 360 o