Union or combine multiple circle google map api

Question

How to union multiple circle google map with different color?

Screenshot the case is picture below

I have some circle with different color, and i wanna union between red cirlce with yellow circle

 what sould I do? anybody have a references? thanks for your attention

Answer 1

Please check this reference for combine two union circle : http://jsfiddle.net/2hnrqdpt/