# the area of an irregular cyclic polygon from given corner point angles!!!! [duplicate]

This question is an exact duplicate of:

how can I calculate the area of an irregular cyclic polygon from given corner point angles ? I have a corner point angles given to me in the question. Also, What i need is a formula for finding an area of an irregular cyclic polygon by using corner point angles.

in order to do my c++ homework, I have to solve this first. enter image description here

## marked as duplicate by Blue, Martin R, Joel Reyes Noche, user91500, quid♦Oct 25 '15 at 11:36

This question was marked as an exact duplicate of an existing question.

• Please add the relevant information to the question itself instead of links to screenshots. Don't forget to add your thoughts and attempts to solve the problem. – Martin R Oct 25 '15 at 8:55
• i added a picture to explain my question more. – Fahad Albalawi Oct 25 '15 at 8:58
• You have already asked this question. – Blue Oct 25 '15 at 9:12
• In addition, I have that question answered. – Mick Oct 25 '15 at 9:35

you can calculate the area triangle by triange. Using the Heron formula, we have, for each triangle $OAB$ $A=\sqrt{s(s-OA)(s-OB)(s-AB)},\quad s=\frac{OA+OB+OC}{2}$
With $OA=OB=1$, we have $s=\frac{AB}{2}+1$
$A=\sqrt{s(s-OA)(s-OB)(s-AB)}=\sqrt{(\frac{AB}{2}+1)(\frac{AB}{2})(\frac{AB}{2})(1-\frac{AB}{2})}=\frac{1}{4}AB \sqrt{4-AB^2}$
Now you just have to find the formula to have $AB$