In Fig 8.105, AB, CD and 1 and 2 are in the ratio 3 : 2. Determine all angles from 1 to 8.

Let, 1 = 3x

2 = 2x


1 + 2 = 180o(Linear pair)


3x + 2x = 180o


5x = 180o


x = 36o


Therefore,


1 = 3x = 108o


2 = 2x = 72o


Vertically opposite angles are equal, so:


1 = 3 = 108o


2 = 4 = 72o


5 = 7 = 108o


6 = 8 = 72o


Corresponding angles:


1 = 5 = 108o


2 = 6 = 72o


1