Question

Can anyone help me with this proof? I'm not so sure I understand this bit (pic attached)

Answer 1

here's the pic

Answer 2

If you look at the isosceles triangle AOP, the angle AOP must be 180-2x, where x is the base angle.
The line QOP is a straight angle, thus AOP + AOQ = 180
--> 180-2x + AOQ = 180
--> AOQ = 2x

Answer 3

excellent! i see it now!

thanks very much :)