I am having trouble aligning my objects and I just rely on my eye to have them aligned. What I really want is to have the three "red" intersection to be equal in size

Please see image below.

I wanted the three circles to intersect at some point but I am not sure if they do intersect equally.

Here's what I did.

I align the top of the the two circle above and have them intersect at some point. And then align the bottom circle and have them intersect the two.

I just rely on my eye to see if they are aligned but I am thinking if illustrator has some tool to do this.