You can have the second circle be centred anywhere on the first, I've just chosen the point .
It's important to note that the equations of the circles are
By subtracting the first equation from the second we find
So the equations intersect at .
Putting the equations as in terms of gives:
Since these are symmetrical about the axis, we can work out the areas enclosed by the above semicircles, and then double it.
So we can finally say:
You will need to use trigonometric substitution to solve these.
Try for the first
and for the second.