thank you

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- Dec 9th 2008, 12:13 AMhelloyingAngles in circle
thank you

- Dec 9th 2008, 02:36 AMGrandadAngles in circles
Hi -

This is a bit tricky. You need to suppose angle FCD =*x*. Then angle BCE is also*x*(vertically opposite angles).

Then you can use the following facts to find an equation for*x*:

- The
*exterior*angle of a triangle is equal to the sum of the*interior opposite*angles. (So, for instance, angle ADC = 32 +*x*) - The
*opposite angles*of a cyclic quadrilateral are*supplementary*. (So, for instance, angle ADC + angle ABC = 180 degrees.)

When you've got*x*you can now use the fact that:

- The
*exterior*angle of a cyclic quadrilateral is equal to the*opposite interior*angle. (So, for instance, angle DAB = angle FCD.)

I hope you can work it out from here.

Grandad - The